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Accumulation point

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It does not make a difference if we restrict the condition to open neighbourhoods only. It is often convenient to use the "open neighbourhood" form of the definition to show that a point is a limit point and to use the "general neighbourhood" form of the definition to derive facts from a known limit
3907: 3026: 488:). Importantly, although "limit point of a set" is synonymous with "cluster/accumulation point of a set", this is not true for sequences (nor nets or filters). That is, the term "limit point of a sequence" is 782:. Indeed, a set is closed if and only if it contains all of its limit points, and the topological closure operation can be thought of as an operation that enriches a set by uniting it with its limit points. 2892: 1989: 3200: 3490: 3349: 3289: 3132: 3253: 2953: 858: 3807: 307: 3720: 2177: 4222: 4167: 4000: 2488: 2063: 6218: 1418: 2375: 6157: 5072: 3961: 3448: 3378: 2325: 910: 765: 687: 2721: 2688: 2246: 2210: 2099: 449: 2759: 2520: 5958: 3608: 3513: 3313: 1766: 3935: 3584: 3056: 2570: 1908: 1362: 1211: 5929: 5903: 5740: 4854: 4671: 4369: 1301: 1179: 665: 5101: 4254: 3802: 3773: 711: 6304: 6241: 6180: 6111: 6001: 5783: 5659: 5616: 5573: 5530: 5447: 5364: 5321: 5278: 5235: 5192: 5124: 4957: 4802: 4759: 4716: 4579: 4556: 4513: 4470: 4427: 4277: 4112: 4049: 3401: 3155: 2806: 2035: 1882: 1840: 1789: 1694: 1645: 1596: 1545: 1495: 1445: 1274: 985: 393: 244: 6281: 6261: 6131: 6088: 6068: 6048: 6024: 5978: 5877: 5857: 5830: 5806: 5760: 5714: 5679: 5636: 5593: 5550: 5507: 5487: 5467: 5424: 5404: 5384: 5341: 5298: 5255: 5212: 5169: 5149: 5031: 5011: 4981: 4934: 4914: 4894: 4874: 4822: 4779: 4736: 4693: 4639: 4619: 4599: 4533: 4490: 4447: 4404: 4337: 4317: 4297: 4187: 4132: 4089: 4069: 4026: 3740: 3668: 3648: 3628: 3553: 3533: 3421: 3220: 3096: 3076: 2912: 2779: 2652: 2632: 2609: 2544: 2426: 2406: 2345: 2298: 2266: 2139: 2119: 2012: 1809: 1736: 1716: 1665: 1618: 1565: 1522: 1468: 1382: 1324: 1251: 1231: 1151: 1124: 1104: 1084: 1060: 1025: 1005: 959: 639: 608: 588: 568: 548: 524: 413: 370: 350: 330: 221: 201: 181: 161: 137: 117: 97: 74: 743: 2961: 3295:
If no element occurs infinitely many times in the sequence, for example if all the elements are distinct, any accumulation point of the sequence is an
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is an accumulation point of any of the corresponding sequences (because any neighborhood of the point will contain infinitely many elements of
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We use the fact that a point is in the closure of a set if and only if every neighborhood of the point meets the set. Now,
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of a non-constant sequence is an accumulation point of the sequence. And by definition, every limit point is an
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cannot be an accumulation point of any of the associated sequences without infinite repeats (because
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is discrete, then every point is isolated and cannot be a limit point of any set. Conversely, if
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Cluster points in nets encompass the idea of both condensation points and ω-accumulation points.
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However, a set can not have a non-trivial intersection with its complement. Conversely, assume
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contains all but finitely many elements of the sequence). That is why we do not use the term
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with standard topology (for a less trivial example of a limit point, see the first caption).
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here), viz. -1 and +1. Thus, thinking of sets, these points are limit points of the set
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can be expressed as a union of open neighbourhoods of the points in the complement of
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has a neighborhood that contains only finitely many (possibly even none) points of
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Relation between accumulation point of a sequence and accumulation point of a set
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This definition of a cluster or accumulation point of a sequence generalizes to
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itself. A limit point can be characterized as an adherent point that is not an
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and that neighborhood can only contain finitely many terms of such sequences).
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A corollary of this result gives us a characterisation of closed sets: A set
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in many ways, even with repeats, and thus associate with it many sequences
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contains all its limit points. We shall show that the complement of
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The set of all cluster points of a sequence is sometimes called the
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In fact, Fréchet–Urysohn spaces are characterized by this property.
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is not a limit point, and hence there exists an open neighbourhood
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of a sequence as a synonym for accumulation point of the sequence.
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and hence also infinitely many terms in any associated sequence).
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For example, if the sequence is the constant sequence with value
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to which the sequence converges (that is, every neighborhood of
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is closed if and only if it contains all of its limit points.
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then we have the following characterization of the closure of
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synonymous with "cluster/accumulation point of a sequence".
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need not be an accumulation point of the corresponding set
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is a limit point (though not a boundary point) of interval
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may have a neighbourhood not containing points other than
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Pages displaying short descriptions of redirect targets
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is a boundary point (but not a limit point) of the set
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Limit points of a set should also not be confused with
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The limit points of a set should not be confused with
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that is not open. Hence, every open neighbourhood of
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It is equivalent to say that for every neighbourhood
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Pages displaying wikidata descriptions as a fallback
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This concept profitably generalizes the notion of a
3058:that occurs infinitely many times in the sequence, 6298: 6275: 6255: 6235: 6212: 6174: 6151: 6125: 6105: 6082: 6062: 6042: 6018: 5995: 5972: 5952: 5923: 5897: 5871: 5851: 5824: 5800: 5777: 5754: 5734: 5708: 5673: 5653: 5630: 5610: 5587: 5567: 5544: 5524: 5501: 5481: 5461: 5441: 5418: 5398: 5378: 5358: 5335: 5315: 5292: 5272: 5249: 5229: 5206: 5186: 5163: 5143: 5118: 5095: 5066: 5025: 5005: 4975: 4951: 4928: 4908: 4888: 4868: 4848: 4816: 4796: 4773: 4753: 4730: 4710: 4687: 4665: 4633: 4613: 4593: 4573: 4550: 4527: 4507: 4484: 4464: 4441: 4421: 4398: 4363: 4331: 4311: 4291: 4271: 4248: 4216: 4181: 4161: 4126: 4106: 4083: 4063: 4043: 4020: 3994: 3955: 3929: 3901: 3796: 3767: 3734: 3714: 3662: 3642: 3622: 3602: 3578: 3547: 3527: 3507: 3485:{\displaystyle A=\operatorname {Im} x_{\bullet }.} 3484: 3442: 3415: 3395: 3372: 3343: 3307: 3283: 3247: 3214: 3194: 3149: 3126: 3090: 3070: 3050: 3020: 2947: 2906: 2886: 2800: 2773: 2753: 2715: 2682: 2646: 2626: 2603: 2564: 2538: 2514: 2482: 2420: 2400: 2369: 2339: 2319: 2292: 2260: 2240: 2204: 2171: 2133: 2113: 2093: 2057: 2029: 2006: 1983: 1902: 1876: 1834: 1803: 1783: 1760: 1730: 1710: 1688: 1659: 1639: 1612: 1590: 1559: 1539: 1516: 1489: 1462: 1439: 1412: 1376: 1356: 1318: 1295: 1268: 1245: 1225: 1205: 1173: 1145: 1118: 1098: 1078: 1054: 1019: 999: 979: 953: 904: 852: 759: 737: 705: 681: 659: 633: 602: 582: 562: 542: 518: 443: 407: 387: 364: 344: 324: 301: 238: 215: 195: 175: 155: 131: 111: 91: 68: 6366: â€“ Value to which tends an infinite sequence 6070:with more than one element, then all elements of 7011: 3344:{\displaystyle \operatorname {Im} x_{\bullet }.} 3284:{\displaystyle \operatorname {Im} x_{\bullet }.} 3127:{\displaystyle \operatorname {Im} x_{\bullet }.} 3248:{\displaystyle \operatorname {Im} x_{\bullet }} 1853:Net (mathematics) § Cluster point of a net 920: 3078:is an accumulation point of the sequence. But 2948:{\displaystyle x_{\bullet }:\mathbb {N} \to X} 853:{\displaystyle x_{n}=(-1)^{n}{\frac {n}{n+1}}} 6626: 550:. Unlike for limit points, an adherent point 6207: 6201: 5918: 5912: 5892: 5886: 5729: 5723: 5343:should have a non-trivial intersection with 4208: 4202: 4153: 4147: 3986: 3980: 3189: 3183: 1567:is a specific type of limit point called an 1500:Special types of accumulation point of a set 1407: 1401: 1303:spaces are characterized by this property. 896: 883: 774:and is the underpinning of concepts such as 654: 648: 246:There is also a closely related concept for 5879:is not discrete, then there is a singleton 3354:Conversely, given a countable infinite set 1811:is a specific type of limit point called a 1667:is a specific type of limit point called a 476:) by definition refers to a point that the 302:{\displaystyle (x_{n})_{n\in \mathbb {N} }} 6994: 6967: 6633: 6619: 3315:-accumulation point of the associated set 395:there are infinitely many natural numbers 3009: 2935: 2384:Note that there is already the notion of 2162: 2051: 1845:Accumulation points of sequences and nets 753: 675: 293: 223:does not itself have to be an element of 36:Limit (disambiguation) § Mathematics 6524: 6482: 6401: 6389: 6342: â€“ Set of all limit points of a set 6324: â€“ a stronger analog of limit point 5575:Since this argument holds for arbitrary 924: 784: 119:that can be "approximated" by points of 6554: 6466: 5033:is equal to its closure if and only if 14: 7012: 3715:{\displaystyle \operatorname {cl} (S)} 2172:{\displaystyle n_{0}\in \mathbb {N} ,} 1233:if and only if every neighbourhood of 6614: 6372: â€“ The limit of some subsequence 4256:to denote the set of limit points of 4114:if and only if every neighborhood of 4051:if and only if every neighborhood of 3403:we can enumerate all the elements of 6133:is a singleton, then every point of 4371:This fact is sometimes taken as the 929:A sequence enumerating all positive 27:Cluster point in a topological space 5762:that contains no points other than 5552:lies entirely in the complement of 5257:comprises an open neighbourhood of 1524:contains infinitely many points of 1253:contains infinitely many points of 793:, the sequence of rational numbers 506:) for which every neighbourhood of 352:such that, for every neighbourhood 24: 3893: 3028:can be defined in the usual way. 2879: 2347:is a limit of some subsequence of 1976: 25: 7041: 6443:"Examples of Accumulation Points" 6220:is nonempty, its closure will be 6198: 6143: 4217:{\displaystyle S\setminus \{x\}.} 4199: 4162:{\displaystyle S\setminus \{x\},} 4144: 3995:{\displaystyle S\setminus \{x\}.} 3977: 3255:and not an accumulation point of 2483:{\displaystyle f:(P,\leq )\to X,} 2058:{\displaystyle n\in \mathbb {N} } 1398: 6993: 6966: 6956: 6946: 6935: 6925: 6924: 6718: 6213:{\displaystyle S\setminus \{x\}} 5426:be a point in the complement of 2546:is a topological space. A point 1922:accumulation point of a sequence 1413:{\displaystyle S\setminus \{x\}} 462:The similarly named notion of a 3862: 3856: 1086:contains at least one point of 203:itself. A limit point of a set 6489:General Topology: Chapters 1–4 6435: 6421: 6407: 5090: 5084: 5061: 5055: 4840: 4834: 4657: 4651: 4355: 4349: 4243: 4237: 3887: 3881: 3872: 3866: 3853: 3847: 3838: 3832: 3823: 3817: 3791: 3785: 3762: 3756: 3709: 3703: 2939: 2739: 2733: 2509: 2497: 2471: 2468: 2456: 823: 813: 732: 720: 282: 268: 13: 1: 6476: 5689:is a limit point of any set. 3674: 2370:{\displaystyle x_{\bullet }.} 1039:accumulation point of the set 915: 6640: 6445:. 2021-01-13. Archived from 6376: 6152:{\displaystyle X\setminus S} 5812:if and only if no subset of 5067:{\displaystyle S=S\cup L(S)} 4856:then every neighbourhood of 4718:then every neighbourhood of 4515:then every neighbourhood of 3963:if and only if it is in the 3956:{\displaystyle S\subseteq X} 3443:{\displaystyle x_{\bullet }} 3373:{\displaystyle A\subseteq X} 2914:is by definition just a map 2320:{\displaystyle x_{\bullet }} 921:Accumulation points of a set 905:{\displaystyle S=\{x_{n}\}.} 760:{\displaystyle \mathbb {R} } 682:{\displaystyle \mathbb {R} } 7: 6599:Encyclopedia of Mathematics 6532:. Boston: Allyn and Bacon. 6309: 5716:is an isolated point, then 4936:is again in the closure of 3032:If there exists an element 2716:{\displaystyle p\geq p_{0}} 2683:{\displaystyle p_{0}\in P,} 2587:accumulation point of a net 2241:{\displaystyle x_{n}\in V.} 2205:{\displaystyle n\geq n_{0}} 2094:{\displaystyle x_{n}\in V.} 1815:complete accumulation point 1450:The set of limit points of 444:{\displaystyle x_{n}\in V.} 10: 7046: 6887:Banach fixed-point theorem 5323:any open neighbourhood of 4959:This completes the proof. 2754:{\displaystyle f(p)\in V,} 2439:generalizes the idea of a 2037:there are infinitely many 1850: 1768:equals the cardinality of 1600:If every neighbourhood of 1504:If every neighbourhood of 1384:if and only if there is a 789:With respect to the usual 29: 6920: 6877: 6841: 6727: 6716: 6648: 6340:Derived set (mathematics) 6283:is the unique element of 5013:is closed if and only if 4558:and this point cannot be 4319:is equal to the union of 2515:{\displaystyle (P,\leq )} 1857:Cluster point of a filter 465:limit point of a sequence 6500:ÉlĂ©ments de mathĂ©matique 5953:{\displaystyle y\neq x,} 5661:Hence the complement of 5509:that does not intersect 4386:("Left subset") Suppose 3222:is an isolated point of 139:in the sense that every 6429:"What is a limit point" 5237:then the complement to 3610:-accumulation point of 3603:{\displaystyle \omega } 3515:-accumulation point of 3508:{\displaystyle \omega } 3308:{\displaystyle \omega } 2276:(or, more generally, a 1861:In a topological space 1761:{\displaystyle U\cap S} 1698:If every neighbourhood 470:limit point of a filter 6942:Mathematics portal 6842:Metrics and properties 6828:Second-countable space 6594:"Limit point of a set" 6564:Upper Saddle River, NJ 6300: 6277: 6257: 6243:It is only empty when 6237: 6214: 6176: 6153: 6127: 6107: 6084: 6064: 6044: 6020: 5997: 5974: 5954: 5925: 5899: 5873: 5853: 5826: 5802: 5779: 5756: 5742:is a neighbourhood of 5736: 5710: 5675: 5655: 5632: 5612: 5589: 5569: 5546: 5526: 5503: 5483: 5463: 5443: 5420: 5400: 5380: 5360: 5337: 5317: 5294: 5274: 5251: 5231: 5208: 5188: 5165: 5145: 5120: 5097: 5068: 5027: 5007: 4977: 4953: 4930: 4910: 4890: 4870: 4850: 4818: 4798: 4775: 4755: 4732: 4712: 4689: 4667: 4635: 4615: 4595: 4575: 4552: 4529: 4509: 4486: 4466: 4443: 4423: 4400: 4365: 4333: 4313: 4293: 4273: 4250: 4218: 4183: 4163: 4128: 4108: 4085: 4065: 4045: 4022: 3996: 3957: 3931: 3930:{\displaystyle x\in X} 3903: 3798: 3769: 3736: 3716: 3664: 3644: 3624: 3604: 3580: 3579:{\displaystyle x\in X} 3549: 3529: 3509: 3486: 3444: 3417: 3397: 3374: 3345: 3309: 3285: 3249: 3216: 3196: 3151: 3128: 3092: 3072: 3052: 3051:{\displaystyle x\in X} 3022: 2949: 2908: 2888: 2802: 2775: 2755: 2717: 2684: 2648: 2628: 2605: 2566: 2565:{\displaystyle x\in X} 2540: 2516: 2484: 2443:. A net is a function 2422: 2402: 2371: 2341: 2321: 2300:is a cluster point of 2294: 2262: 2242: 2206: 2173: 2135: 2115: 2095: 2059: 2031: 2008: 1985: 1904: 1903:{\displaystyle x\in X} 1878: 1836: 1805: 1785: 1762: 1732: 1712: 1690: 1661: 1641: 1614: 1592: 1561: 1541: 1518: 1491: 1464: 1441: 1414: 1378: 1358: 1357:{\displaystyle x\in X} 1336:first-countable spaces 1320: 1297: 1270: 1247: 1227: 1207: 1206:{\displaystyle x\in X} 1175: 1147: 1120: 1100: 1080: 1056: 1021: 1001: 981: 955: 938: 912: 906: 854: 761: 739: 707: 683: 661: 635: 604: 584: 564: 544: 520: 445: 409: 389: 366: 346: 326: 303: 240: 217: 197: 177: 157: 133: 113: 93: 70: 6301: 6278: 6258: 6238: 6215: 6177: 6154: 6128: 6108: 6085: 6065: 6045: 6021: 5998: 5975: 5955: 5926: 5924:{\displaystyle \{x\}} 5900: 5898:{\displaystyle \{x\}} 5874: 5854: 5827: 5803: 5780: 5757: 5737: 5735:{\displaystyle \{x\}} 5711: 5676: 5656: 5633: 5613: 5595:in the complement of 5590: 5570: 5547: 5527: 5504: 5484: 5464: 5444: 5421: 5401: 5381: 5361: 5338: 5318: 5295: 5275: 5252: 5232: 5209: 5189: 5166: 5146: 5121: 5098: 5069: 5028: 5008: 4978: 4954: 4931: 4911: 4891: 4871: 4851: 4849:{\displaystyle L(S),} 4819: 4799: 4781:is in the closure of 4776: 4756: 4733: 4713: 4690: 4668: 4666:{\displaystyle L(S).} 4636: 4616: 4596: 4576: 4553: 4530: 4510: 4487: 4467: 4444: 4424: 4406:is in the closure of 4401: 4366: 4364:{\displaystyle L(S).} 4334: 4314: 4294: 4274: 4251: 4219: 4189:is in the closure of 4184: 4164: 4129: 4109: 4086: 4066: 4046: 4023: 3997: 3958: 3932: 3904: 3799: 3770: 3737: 3717: 3665: 3645: 3625: 3605: 3581: 3550: 3530: 3510: 3487: 3445: 3418: 3398: 3375: 3346: 3310: 3286: 3250: 3217: 3197: 3152: 3129: 3093: 3073: 3053: 3023: 2950: 2909: 2889: 2816:are also defined for 2803: 2776: 2756: 2718: 2685: 2649: 2629: 2606: 2567: 2541: 2517: 2485: 2423: 2403: 2372: 2342: 2322: 2295: 2278:FrĂ©chet–Urysohn space 2274:first-countable space 2263: 2243: 2207: 2174: 2136: 2116: 2096: 2060: 2032: 2009: 1986: 1905: 1879: 1837: 1806: 1786: 1763: 1733: 1713: 1691: 1662: 1642: 1615: 1593: 1562: 1542: 1519: 1492: 1465: 1442: 1415: 1379: 1359: 1328:FrĂ©chet–Urysohn space 1321: 1298: 1296:{\displaystyle T_{1}} 1271: 1248: 1228: 1208: 1176: 1174:{\displaystyle T_{1}} 1148: 1121: 1101: 1081: 1057: 1022: 1002: 982: 956: 928: 907: 855: 788: 762: 740: 708: 684: 662: 660:{\displaystyle \{0\}} 636: 605: 585: 565: 545: 521: 478:sequence converges to 446: 410: 390: 367: 347: 327: 304: 241: 218: 198: 178: 158: 134: 114: 94: 71: 6897:Invariance of domain 6849:Euler characteristic 6823:Bundle (mathematics) 6287: 6267: 6247: 6224: 6192: 6163: 6159:is a limit point of 6137: 6117: 6094: 6090:are limit points of 6074: 6054: 6034: 6010: 5984: 5980:is a limit point of 5964: 5935: 5909: 5883: 5863: 5843: 5816: 5792: 5766: 5746: 5720: 5700: 5665: 5642: 5622: 5599: 5579: 5556: 5536: 5513: 5493: 5473: 5453: 5430: 5410: 5406:is an open set. Let 5390: 5370: 5347: 5327: 5304: 5300:is a limit point of 5284: 5261: 5241: 5218: 5198: 5175: 5155: 5151:be a closed set and 5135: 5107: 5096:{\displaystyle L(S)} 5078: 5037: 5017: 4997: 4967: 4940: 4920: 4900: 4880: 4876:contains a point of 4860: 4828: 4808: 4785: 4765: 4742: 4722: 4699: 4679: 4675:("Right subset") If 4645: 4625: 4605: 4601:is a limit point of 4585: 4562: 4539: 4535:contains a point of 4519: 4496: 4476: 4453: 4433: 4410: 4390: 4343: 4323: 4303: 4283: 4260: 4249:{\displaystyle L(S)} 4231: 4193: 4173: 4138: 4134:contains a point of 4118: 4095: 4075: 4071:contains a point of 4055: 4032: 4028:is a limit point of 4012: 3971: 3941: 3937:is a limit point of 3915: 3808: 3797:{\displaystyle I(S)} 3779: 3775:and isolated points 3768:{\displaystyle L(S)} 3750: 3746:of its limit points 3726: 3694: 3654: 3634: 3614: 3594: 3564: 3539: 3519: 3499: 3454: 3427: 3407: 3384: 3358: 3319: 3299: 3259: 3226: 3206: 3161: 3138: 3102: 3082: 3062: 3036: 2962: 2918: 2898: 2832: 2789: 2765: 2727: 2694: 2658: 2638: 2618: 2595: 2550: 2530: 2494: 2447: 2412: 2392: 2351: 2331: 2304: 2284: 2252: 2216: 2183: 2145: 2125: 2105: 2069: 2041: 2018: 1998: 1929: 1888: 1865: 1823: 1795: 1772: 1746: 1722: 1702: 1677: 1651: 1628: 1604: 1579: 1571:ω-accumulation point 1551: 1528: 1508: 1478: 1454: 1428: 1392: 1368: 1364:is a limit point of 1342: 1310: 1280: 1257: 1237: 1217: 1213:is a limit point of 1191: 1158: 1137: 1110: 1090: 1070: 1046: 1011: 991: 968: 945: 874: 797: 749: 717: 697: 671: 645: 625: 594: 574: 554: 534: 510: 474:limit point of a net 419: 399: 376: 356: 336: 316: 265: 227: 207: 187: 167: 163:contains a point of 147: 123: 103: 83: 60: 18:Limit point of a set 6907:Tychonoff's theorem 6902:PoincarĂ© conjecture 6656:General (point-set) 6562:(Second ed.). 6392:, pp. 209–210. 6370:Subsequential limit 6364:Limit of a sequence 6358:Limit of a function 6346:Filters in topology 5832:has a limit point. 2883: 2785:which converges to 2386:limit of a sequence 1980: 937:is a cluster point. 780:topological closure 706:{\displaystyle 0.5} 482:filter converges to 480:(respectively, the 32:Limit (mathematics) 6892:De Rham cohomology 6813:Polyhedral complex 6803:Simplicial complex 6568:Prentice Hall, Inc 6495:Topologie GĂ©nĂ©rale 6469:, pp. 97–102. 6322:Condensation point 6299:{\displaystyle S.} 6296: 6273: 6253: 6236:{\displaystyle X.} 6233: 6210: 6186: 6175:{\displaystyle S.} 6172: 6149: 6123: 6106:{\displaystyle S.} 6103: 6080: 6060: 6040: 6016: 5996:{\displaystyle X.} 5993: 5970: 5950: 5921: 5895: 5869: 5849: 5837: 5822: 5798: 5778:{\displaystyle x.} 5775: 5752: 5732: 5706: 5694: 5671: 5654:{\displaystyle S.} 5651: 5628: 5618:the complement of 5611:{\displaystyle S,} 5608: 5585: 5568:{\displaystyle S.} 5565: 5542: 5525:{\displaystyle S,} 5522: 5499: 5479: 5459: 5442:{\displaystyle S.} 5439: 5416: 5396: 5376: 5359:{\displaystyle S.} 5356: 5333: 5316:{\displaystyle S,} 5313: 5290: 5273:{\displaystyle x.} 5270: 5247: 5230:{\displaystyle S,} 5227: 5204: 5187:{\displaystyle S.} 5184: 5161: 5141: 5119:{\displaystyle S.} 5116: 5093: 5064: 5023: 5003: 4988: 4973: 4952:{\displaystyle S.} 4949: 4926: 4906: 4886: 4866: 4846: 4814: 4797:{\displaystyle S.} 4794: 4771: 4754:{\displaystyle S,} 4751: 4728: 4711:{\displaystyle S,} 4708: 4685: 4663: 4631: 4611: 4591: 4574:{\displaystyle x.} 4571: 4551:{\displaystyle S,} 4548: 4525: 4508:{\displaystyle S,} 4505: 4482: 4465:{\displaystyle S,} 4462: 4439: 4422:{\displaystyle S.} 4419: 4396: 4384: 4361: 4329: 4309: 4289: 4272:{\displaystyle S,} 4269: 4246: 4214: 4179: 4159: 4124: 4107:{\displaystyle x,} 4104: 4081: 4061: 4044:{\displaystyle S,} 4041: 4018: 4006: 3992: 3953: 3927: 3899: 3794: 3765: 3732: 3712: 3660: 3640: 3620: 3600: 3576: 3545: 3525: 3505: 3482: 3450:that will satisfy 3440: 3413: 3396:{\displaystyle X,} 3393: 3370: 3341: 3305: 3281: 3245: 3212: 3192: 3150:{\displaystyle x,} 3147: 3124: 3088: 3068: 3048: 3018: 2945: 2904: 2884: 2848: 2801:{\displaystyle x.} 2798: 2771: 2751: 2713: 2680: 2644: 2624: 2601: 2562: 2536: 2512: 2480: 2418: 2398: 2367: 2337: 2317: 2290: 2258: 2238: 2202: 2169: 2131: 2111: 2091: 2055: 2030:{\displaystyle x,} 2027: 2004: 1981: 1945: 1900: 1877:{\displaystyle X,} 1874: 1835:{\displaystyle S.} 1832: 1801: 1784:{\displaystyle S,} 1781: 1758: 1728: 1708: 1689:{\displaystyle S.} 1686: 1670:condensation point 1657: 1640:{\displaystyle S,} 1637: 1610: 1591:{\displaystyle S.} 1588: 1557: 1540:{\displaystyle S,} 1537: 1514: 1490:{\displaystyle S.} 1487: 1460: 1440:{\displaystyle x.} 1437: 1410: 1374: 1354: 1316: 1293: 1269:{\displaystyle S.} 1266: 1243: 1223: 1203: 1171: 1143: 1116: 1096: 1076: 1052: 1017: 997: 980:{\displaystyle X.} 977: 951: 939: 913: 902: 850: 791:Euclidean topology 757: 735: 703: 679: 657: 631: 600: 580: 560: 540: 516: 441: 405: 388:{\displaystyle x,} 385: 362: 342: 322: 299: 256:accumulation point 239:{\displaystyle S.} 236: 213: 193: 173: 153: 129: 109: 89: 66: 47:accumulation point 41:In mathematics, a 7007: 7006: 6796:fundamental group 6577:978-0-13-181629-9 6556:Munkres, James R. 6539:978-0-697-06889-7 6509:978-3-540-64241-1 6484:Bourbaki, Nicolas 6404:, pp. 68–83. 6331:Convergent filter 6276:{\displaystyle x} 6256:{\displaystyle S} 6184: 6126:{\displaystyle S} 6083:{\displaystyle X} 6063:{\displaystyle X} 6043:{\displaystyle S} 6019:{\displaystyle X} 5973:{\displaystyle x} 5931:contains a point 5872:{\displaystyle X} 5852:{\displaystyle X} 5835: 5825:{\displaystyle X} 5801:{\displaystyle X} 5755:{\displaystyle x} 5709:{\displaystyle x} 5692: 5674:{\displaystyle S} 5631:{\displaystyle S} 5588:{\displaystyle x} 5545:{\displaystyle U} 5502:{\displaystyle x} 5482:{\displaystyle U} 5462:{\displaystyle x} 5419:{\displaystyle x} 5399:{\displaystyle S} 5379:{\displaystyle S} 5336:{\displaystyle x} 5293:{\displaystyle x} 5250:{\displaystyle S} 5207:{\displaystyle x} 5171:a limit point of 5164:{\displaystyle x} 5144:{\displaystyle S} 5026:{\displaystyle S} 5006:{\displaystyle S} 4986: 4976:{\displaystyle S} 4929:{\displaystyle x} 4909:{\displaystyle x} 4889:{\displaystyle S} 4869:{\displaystyle x} 4817:{\displaystyle x} 4774:{\displaystyle x} 4731:{\displaystyle x} 4688:{\displaystyle x} 4634:{\displaystyle x} 4614:{\displaystyle S} 4594:{\displaystyle x} 4528:{\displaystyle x} 4485:{\displaystyle x} 4442:{\displaystyle x} 4399:{\displaystyle x} 4382: 4332:{\displaystyle S} 4312:{\displaystyle S} 4299:: The closure of 4292:{\displaystyle S} 4182:{\displaystyle x} 4127:{\displaystyle x} 4084:{\displaystyle S} 4064:{\displaystyle x} 4021:{\displaystyle x} 4004: 3860: 3735:{\displaystyle S} 3663:{\displaystyle A} 3643:{\displaystyle x} 3623:{\displaystyle A} 3548:{\displaystyle A} 3528:{\displaystyle A} 3416:{\displaystyle A} 3215:{\displaystyle x} 3091:{\displaystyle x} 3071:{\displaystyle x} 2907:{\displaystyle X} 2774:{\displaystyle f} 2761:equivalently, if 2647:{\displaystyle x} 2627:{\displaystyle V} 2604:{\displaystyle f} 2539:{\displaystyle X} 2435:The concept of a 2421:{\displaystyle x} 2401:{\displaystyle x} 2340:{\displaystyle x} 2293:{\displaystyle x} 2261:{\displaystyle X} 2134:{\displaystyle x} 2114:{\displaystyle V} 2007:{\displaystyle V} 1804:{\displaystyle x} 1738:is such that the 1731:{\displaystyle x} 1711:{\displaystyle U} 1660:{\displaystyle x} 1613:{\displaystyle x} 1560:{\displaystyle x} 1517:{\displaystyle x} 1463:{\displaystyle S} 1377:{\displaystyle S} 1319:{\displaystyle X} 1246:{\displaystyle x} 1226:{\displaystyle S} 1146:{\displaystyle X} 1119:{\displaystyle x} 1099:{\displaystyle S} 1079:{\displaystyle x} 1055:{\displaystyle S} 1020:{\displaystyle X} 1000:{\displaystyle x} 963:topological space 961:be a subset of a 954:{\displaystyle S} 848: 691:standard topology 634:{\displaystyle 0} 603:{\displaystyle x} 583:{\displaystyle S} 563:{\displaystyle x} 543:{\displaystyle S} 519:{\displaystyle x} 468:(respectively, a 408:{\displaystyle n} 365:{\displaystyle V} 345:{\displaystyle x} 325:{\displaystyle X} 311:topological space 216:{\displaystyle S} 196:{\displaystyle x} 176:{\displaystyle S} 156:{\displaystyle x} 132:{\displaystyle S} 112:{\displaystyle x} 92:{\displaystyle X} 78:topological space 69:{\displaystyle S} 16:(Redirected from 7037: 7030:General topology 6997: 6996: 6970: 6969: 6960: 6950: 6940: 6939: 6928: 6927: 6722: 6635: 6628: 6621: 6612: 6611: 6607: 6589: 6551: 6521: 6470: 6464: 6458: 6457: 6455: 6454: 6439: 6433: 6432: 6425: 6419: 6418: 6411: 6405: 6399: 6393: 6387: 6336: 6327: 6305: 6303: 6302: 6297: 6282: 6280: 6279: 6274: 6262: 6260: 6259: 6254: 6242: 6240: 6239: 6234: 6219: 6217: 6216: 6211: 6181: 6179: 6178: 6173: 6158: 6156: 6155: 6150: 6132: 6130: 6129: 6124: 6112: 6110: 6109: 6104: 6089: 6087: 6086: 6081: 6069: 6067: 6066: 6061: 6049: 6047: 6046: 6041: 6028:trivial topology 6025: 6023: 6022: 6017: 6002: 6000: 5999: 5994: 5979: 5977: 5976: 5971: 5959: 5957: 5956: 5951: 5930: 5928: 5927: 5922: 5904: 5902: 5901: 5896: 5878: 5876: 5875: 5870: 5858: 5856: 5855: 5850: 5831: 5829: 5828: 5823: 5807: 5805: 5804: 5799: 5784: 5782: 5781: 5776: 5761: 5759: 5758: 5753: 5741: 5739: 5738: 5733: 5715: 5713: 5712: 5707: 5680: 5678: 5677: 5672: 5660: 5658: 5657: 5652: 5637: 5635: 5634: 5629: 5617: 5615: 5614: 5609: 5594: 5592: 5591: 5586: 5574: 5572: 5571: 5566: 5551: 5549: 5548: 5543: 5531: 5529: 5528: 5523: 5508: 5506: 5505: 5500: 5488: 5486: 5485: 5480: 5468: 5466: 5465: 5460: 5448: 5446: 5445: 5440: 5425: 5423: 5422: 5417: 5405: 5403: 5402: 5397: 5385: 5383: 5382: 5377: 5365: 5363: 5362: 5357: 5342: 5340: 5339: 5334: 5322: 5320: 5319: 5314: 5299: 5297: 5296: 5291: 5279: 5277: 5276: 5271: 5256: 5254: 5253: 5248: 5236: 5234: 5233: 5228: 5213: 5211: 5210: 5205: 5193: 5191: 5190: 5185: 5170: 5168: 5167: 5162: 5150: 5148: 5147: 5142: 5125: 5123: 5122: 5117: 5103:is contained in 5102: 5100: 5099: 5094: 5073: 5071: 5070: 5065: 5032: 5030: 5029: 5024: 5012: 5010: 5009: 5004: 4982: 4980: 4979: 4974: 4958: 4956: 4955: 4950: 4935: 4933: 4932: 4927: 4915: 4913: 4912: 4907: 4895: 4893: 4892: 4887: 4875: 4873: 4872: 4867: 4855: 4853: 4852: 4847: 4823: 4821: 4820: 4815: 4803: 4801: 4800: 4795: 4780: 4778: 4777: 4772: 4760: 4758: 4757: 4752: 4737: 4735: 4734: 4729: 4717: 4715: 4714: 4709: 4694: 4692: 4691: 4686: 4672: 4670: 4669: 4664: 4640: 4638: 4637: 4632: 4620: 4618: 4617: 4612: 4600: 4598: 4597: 4592: 4581:In other words, 4580: 4578: 4577: 4572: 4557: 4555: 4554: 4549: 4534: 4532: 4531: 4526: 4514: 4512: 4511: 4506: 4491: 4489: 4488: 4483: 4472:we are done. If 4471: 4469: 4468: 4463: 4448: 4446: 4445: 4440: 4428: 4426: 4425: 4420: 4405: 4403: 4402: 4397: 4370: 4368: 4367: 4362: 4338: 4336: 4335: 4330: 4318: 4316: 4315: 4310: 4298: 4296: 4295: 4290: 4278: 4276: 4275: 4270: 4255: 4253: 4252: 4247: 4223: 4221: 4220: 4215: 4188: 4186: 4185: 4180: 4168: 4166: 4165: 4160: 4133: 4131: 4130: 4125: 4113: 4111: 4110: 4105: 4090: 4088: 4087: 4082: 4070: 4068: 4067: 4062: 4050: 4048: 4047: 4042: 4027: 4025: 4024: 4019: 4001: 3999: 3998: 3993: 3962: 3960: 3959: 3954: 3936: 3934: 3933: 3928: 3908: 3906: 3905: 3900: 3861: 3858: 3803: 3801: 3800: 3795: 3774: 3772: 3771: 3766: 3741: 3739: 3738: 3733: 3721: 3719: 3718: 3713: 3669: 3667: 3666: 3661: 3649: 3647: 3646: 3641: 3629: 3627: 3626: 3621: 3609: 3607: 3606: 3601: 3585: 3583: 3582: 3577: 3554: 3552: 3551: 3546: 3534: 3532: 3531: 3526: 3514: 3512: 3511: 3506: 3491: 3489: 3488: 3483: 3478: 3477: 3449: 3447: 3446: 3441: 3439: 3438: 3422: 3420: 3419: 3414: 3402: 3400: 3399: 3394: 3379: 3377: 3376: 3371: 3350: 3348: 3347: 3342: 3337: 3336: 3314: 3312: 3311: 3306: 3290: 3288: 3287: 3282: 3277: 3276: 3254: 3252: 3251: 3246: 3244: 3243: 3221: 3219: 3218: 3213: 3201: 3199: 3198: 3193: 3179: 3178: 3156: 3154: 3153: 3148: 3133: 3131: 3130: 3125: 3120: 3119: 3097: 3095: 3094: 3089: 3077: 3075: 3074: 3069: 3057: 3055: 3054: 3049: 3027: 3025: 3024: 3019: 3017: 3013: 3012: 2998: 2997: 2980: 2979: 2954: 2952: 2951: 2946: 2938: 2930: 2929: 2913: 2911: 2910: 2905: 2893: 2891: 2890: 2885: 2882: 2877: 2866: 2862: 2861: 2844: 2843: 2807: 2805: 2804: 2799: 2780: 2778: 2777: 2772: 2760: 2758: 2757: 2752: 2722: 2720: 2719: 2714: 2712: 2711: 2689: 2687: 2686: 2681: 2670: 2669: 2653: 2651: 2650: 2645: 2633: 2631: 2630: 2625: 2610: 2608: 2607: 2602: 2589: 2588: 2579: 2578: 2572:is said to be a 2571: 2569: 2568: 2563: 2545: 2543: 2542: 2537: 2521: 2519: 2518: 2513: 2489: 2487: 2486: 2481: 2427: 2425: 2424: 2419: 2407: 2405: 2404: 2399: 2388:to mean a point 2376: 2374: 2373: 2368: 2363: 2362: 2346: 2344: 2343: 2338: 2326: 2324: 2323: 2318: 2316: 2315: 2299: 2297: 2296: 2291: 2267: 2265: 2264: 2259: 2247: 2245: 2244: 2239: 2228: 2227: 2211: 2209: 2208: 2203: 2201: 2200: 2178: 2176: 2175: 2170: 2165: 2157: 2156: 2140: 2138: 2137: 2132: 2120: 2118: 2117: 2112: 2100: 2098: 2097: 2092: 2081: 2080: 2064: 2062: 2061: 2056: 2054: 2036: 2034: 2033: 2028: 2013: 2011: 2010: 2005: 1990: 1988: 1987: 1982: 1979: 1974: 1963: 1959: 1958: 1941: 1940: 1924: 1923: 1916: 1915: 1910:is said to be a 1909: 1907: 1906: 1901: 1883: 1881: 1880: 1875: 1841: 1839: 1838: 1833: 1817: 1816: 1810: 1808: 1807: 1802: 1790: 1788: 1787: 1782: 1767: 1765: 1764: 1759: 1737: 1735: 1734: 1729: 1717: 1715: 1714: 1709: 1695: 1693: 1692: 1687: 1666: 1664: 1663: 1658: 1646: 1644: 1643: 1638: 1622:uncountably many 1619: 1617: 1616: 1611: 1597: 1595: 1594: 1589: 1573: 1572: 1566: 1564: 1563: 1558: 1546: 1544: 1543: 1538: 1523: 1521: 1520: 1515: 1496: 1494: 1493: 1488: 1469: 1467: 1466: 1461: 1446: 1444: 1443: 1438: 1419: 1417: 1416: 1411: 1383: 1381: 1380: 1375: 1363: 1361: 1360: 1355: 1325: 1323: 1322: 1317: 1302: 1300: 1299: 1294: 1292: 1291: 1275: 1273: 1272: 1267: 1252: 1250: 1249: 1244: 1232: 1230: 1229: 1224: 1212: 1210: 1209: 1204: 1180: 1178: 1177: 1172: 1170: 1169: 1152: 1150: 1149: 1144: 1125: 1123: 1122: 1117: 1105: 1103: 1102: 1097: 1085: 1083: 1082: 1077: 1061: 1059: 1058: 1053: 1041: 1040: 1026: 1024: 1023: 1018: 1006: 1004: 1003: 998: 986: 984: 983: 978: 960: 958: 957: 952: 933:. Each positive 931:rational numbers 911: 909: 908: 903: 895: 894: 859: 857: 856: 851: 849: 847: 833: 831: 830: 809: 808: 766: 764: 763: 758: 756: 744: 742: 741: 738:{\displaystyle } 736: 712: 710: 709: 704: 688: 686: 685: 680: 678: 666: 664: 663: 658: 640: 638: 637: 632: 609: 607: 606: 601: 589: 587: 586: 581: 569: 567: 566: 561: 549: 547: 546: 541: 525: 523: 522: 517: 486:net converges to 450: 448: 447: 442: 431: 430: 414: 412: 411: 406: 394: 392: 391: 386: 371: 369: 368: 363: 351: 349: 348: 343: 331: 329: 328: 323: 308: 306: 305: 300: 298: 297: 296: 280: 279: 245: 243: 242: 237: 222: 220: 219: 214: 202: 200: 199: 194: 182: 180: 179: 174: 162: 160: 159: 154: 138: 136: 135: 130: 118: 116: 115: 110: 98: 96: 95: 90: 75: 73: 72: 67: 21: 7045: 7044: 7040: 7039: 7038: 7036: 7035: 7034: 7010: 7009: 7008: 7003: 6934: 6916: 6912:Urysohn's lemma 6873: 6837: 6723: 6714: 6686:low-dimensional 6644: 6639: 6592: 6578: 6540: 6526:Dugundji, James 6510: 6479: 6474: 6473: 6465: 6461: 6452: 6450: 6441: 6440: 6436: 6427: 6426: 6422: 6413: 6412: 6408: 6400: 6396: 6388: 6384: 6379: 6334: 6325: 6312: 6307: 6288: 6285: 6284: 6268: 6265: 6264: 6248: 6245: 6244: 6225: 6222: 6221: 6193: 6190: 6189: 6164: 6161: 6160: 6138: 6135: 6134: 6118: 6115: 6114: 6095: 6092: 6091: 6075: 6072: 6071: 6055: 6052: 6051: 6050:is a subset of 6035: 6032: 6031: 6011: 6008: 6007: 6004: 5985: 5982: 5981: 5965: 5962: 5961: 5936: 5933: 5932: 5910: 5907: 5906: 5884: 5881: 5880: 5864: 5861: 5860: 5844: 5841: 5840: 5817: 5814: 5813: 5793: 5790: 5789: 5786: 5767: 5764: 5763: 5747: 5744: 5743: 5721: 5718: 5717: 5701: 5698: 5697: 5683: 5666: 5663: 5662: 5643: 5640: 5639: 5623: 5620: 5619: 5600: 5597: 5596: 5580: 5577: 5576: 5557: 5554: 5553: 5537: 5534: 5533: 5514: 5511: 5510: 5494: 5491: 5490: 5474: 5471: 5470: 5454: 5451: 5450: 5449:By assumption, 5431: 5428: 5427: 5411: 5408: 5407: 5391: 5388: 5387: 5371: 5368: 5367: 5348: 5345: 5344: 5328: 5325: 5324: 5305: 5302: 5301: 5285: 5282: 5281: 5262: 5259: 5258: 5242: 5239: 5238: 5219: 5216: 5215: 5199: 5196: 5195: 5176: 5173: 5172: 5156: 5153: 5152: 5136: 5133: 5132: 5108: 5105: 5104: 5079: 5076: 5075: 5074:if and only if 5038: 5035: 5034: 5018: 5015: 5014: 4998: 4995: 4994: 4968: 4965: 4964: 4961: 4941: 4938: 4937: 4921: 4918: 4917: 4901: 4898: 4897: 4881: 4878: 4877: 4861: 4858: 4857: 4829: 4826: 4825: 4809: 4806: 4805: 4786: 4783: 4782: 4766: 4763: 4762: 4743: 4740: 4739: 4723: 4720: 4719: 4700: 4697: 4696: 4680: 4677: 4676: 4646: 4643: 4642: 4626: 4623: 4622: 4606: 4603: 4602: 4586: 4583: 4582: 4563: 4560: 4559: 4540: 4537: 4536: 4520: 4517: 4516: 4497: 4494: 4493: 4477: 4474: 4473: 4454: 4451: 4450: 4434: 4431: 4430: 4411: 4408: 4407: 4391: 4388: 4387: 4344: 4341: 4340: 4324: 4321: 4320: 4304: 4301: 4300: 4284: 4281: 4280: 4261: 4258: 4257: 4232: 4229: 4228: 4225: 4194: 4191: 4190: 4174: 4171: 4170: 4169:if and only if 4139: 4136: 4135: 4119: 4116: 4115: 4096: 4093: 4092: 4076: 4073: 4072: 4056: 4053: 4052: 4033: 4030: 4029: 4013: 4010: 4009: 3972: 3969: 3968: 3942: 3939: 3938: 3916: 3913: 3912: 3857: 3809: 3806: 3805: 3780: 3777: 3776: 3751: 3748: 3747: 3727: 3724: 3723: 3695: 3692: 3691: 3677: 3655: 3652: 3651: 3635: 3632: 3631: 3615: 3612: 3611: 3595: 3592: 3591: 3565: 3562: 3561: 3540: 3537: 3536: 3520: 3517: 3516: 3500: 3497: 3496: 3473: 3469: 3455: 3452: 3451: 3434: 3430: 3428: 3425: 3424: 3408: 3405: 3404: 3385: 3382: 3381: 3359: 3356: 3355: 3332: 3328: 3320: 3317: 3316: 3300: 3297: 3296: 3272: 3268: 3260: 3257: 3256: 3239: 3235: 3227: 3224: 3223: 3207: 3204: 3203: 3174: 3170: 3162: 3159: 3158: 3139: 3136: 3135: 3115: 3111: 3103: 3100: 3099: 3083: 3080: 3079: 3063: 3060: 3059: 3037: 3034: 3033: 3008: 2993: 2989: 2988: 2984: 2975: 2971: 2963: 2960: 2959: 2934: 2925: 2921: 2919: 2916: 2915: 2899: 2896: 2895: 2878: 2867: 2857: 2853: 2849: 2839: 2835: 2833: 2830: 2829: 2828:Every sequence 2826: 2790: 2787: 2786: 2766: 2763: 2762: 2728: 2725: 2724: 2707: 2703: 2695: 2692: 2691: 2665: 2661: 2659: 2656: 2655: 2639: 2636: 2635: 2619: 2616: 2615: 2596: 2593: 2592: 2586: 2585: 2576: 2575: 2551: 2548: 2547: 2531: 2528: 2527: 2495: 2492: 2491: 2448: 2445: 2444: 2413: 2410: 2409: 2393: 2390: 2389: 2358: 2354: 2352: 2349: 2348: 2332: 2329: 2328: 2327:if and only if 2311: 2307: 2305: 2302: 2301: 2285: 2282: 2281: 2253: 2250: 2249: 2223: 2219: 2217: 2214: 2213: 2196: 2192: 2184: 2181: 2180: 2161: 2152: 2148: 2146: 2143: 2142: 2126: 2123: 2122: 2106: 2103: 2102: 2076: 2072: 2070: 2067: 2066: 2050: 2042: 2039: 2038: 2019: 2016: 2015: 1999: 1996: 1995: 1975: 1964: 1954: 1950: 1946: 1936: 1932: 1930: 1927: 1926: 1921: 1920: 1913: 1912: 1889: 1886: 1885: 1866: 1863: 1862: 1859: 1847: 1824: 1821: 1820: 1814: 1813: 1796: 1793: 1792: 1773: 1770: 1769: 1747: 1744: 1743: 1723: 1720: 1719: 1703: 1700: 1699: 1678: 1675: 1674: 1652: 1649: 1648: 1629: 1626: 1625: 1605: 1602: 1601: 1580: 1577: 1576: 1570: 1569: 1552: 1549: 1548: 1529: 1526: 1525: 1509: 1506: 1505: 1502: 1479: 1476: 1475: 1455: 1452: 1451: 1429: 1426: 1425: 1393: 1390: 1389: 1369: 1366: 1365: 1343: 1340: 1339: 1311: 1308: 1307: 1287: 1283: 1281: 1278: 1277: 1258: 1255: 1254: 1238: 1235: 1234: 1218: 1215: 1214: 1192: 1189: 1188: 1165: 1161: 1159: 1156: 1155: 1138: 1135: 1134: 1111: 1108: 1107: 1106:different from 1091: 1088: 1087: 1071: 1068: 1067: 1047: 1044: 1043: 1038: 1037: 1012: 1009: 1008: 992: 989: 988: 969: 966: 965: 946: 943: 942: 923: 918: 890: 886: 875: 872: 871: 837: 832: 826: 822: 804: 800: 798: 795: 794: 752: 750: 747: 746: 718: 715: 714: 698: 695: 694: 674: 672: 669: 668: 646: 643: 642: 626: 623: 622: 621:. For example, 619:boundary points 595: 592: 591: 575: 572: 571: 555: 552: 551: 535: 532: 531: 511: 508: 507: 497:adherent points 426: 422: 420: 417: 416: 400: 397: 396: 377: 374: 373: 357: 354: 353: 337: 334: 333: 317: 314: 313: 292: 285: 281: 275: 271: 266: 263: 262: 228: 225: 224: 208: 205: 204: 188: 185: 184: 168: 165: 164: 148: 145: 144: 124: 121: 120: 104: 101: 100: 84: 81: 80: 61: 58: 57: 39: 28: 23: 22: 15: 12: 11: 5: 7043: 7033: 7032: 7027: 7022: 7005: 7004: 7002: 7001: 6991: 6990: 6989: 6984: 6979: 6964: 6954: 6944: 6932: 6921: 6918: 6917: 6915: 6914: 6909: 6904: 6899: 6894: 6889: 6883: 6881: 6875: 6874: 6872: 6871: 6866: 6861: 6859:Winding number 6856: 6851: 6845: 6843: 6839: 6838: 6836: 6835: 6830: 6825: 6820: 6815: 6810: 6805: 6800: 6799: 6798: 6793: 6791:homotopy group 6783: 6782: 6781: 6776: 6771: 6766: 6761: 6751: 6746: 6741: 6731: 6729: 6725: 6724: 6717: 6715: 6713: 6712: 6707: 6702: 6701: 6700: 6690: 6689: 6688: 6678: 6673: 6668: 6663: 6658: 6652: 6650: 6646: 6645: 6638: 6637: 6630: 6623: 6615: 6609: 6608: 6590: 6576: 6552: 6538: 6522: 6508: 6478: 6475: 6472: 6471: 6459: 6434: 6420: 6406: 6394: 6381: 6380: 6378: 6375: 6374: 6373: 6367: 6361: 6355: 6352:Isolated point 6349: 6343: 6337: 6328: 6319: 6316:Adherent point 6311: 6308: 6295: 6292: 6272: 6252: 6232: 6229: 6209: 6206: 6203: 6200: 6197: 6183: 6171: 6168: 6148: 6145: 6142: 6122: 6102: 6099: 6079: 6059: 6039: 6015: 5992: 5989: 5969: 5949: 5946: 5943: 5940: 5920: 5917: 5914: 5894: 5891: 5888: 5868: 5848: 5834: 5821: 5797: 5774: 5771: 5751: 5731: 5728: 5725: 5705: 5691: 5687:isolated point 5670: 5650: 5647: 5627: 5607: 5604: 5584: 5564: 5561: 5541: 5521: 5518: 5498: 5478: 5458: 5438: 5435: 5415: 5395: 5375: 5355: 5352: 5332: 5312: 5309: 5289: 5269: 5266: 5246: 5226: 5223: 5203: 5183: 5180: 5160: 5140: 5115: 5112: 5092: 5089: 5086: 5083: 5063: 5060: 5057: 5054: 5051: 5048: 5045: 5042: 5022: 5002: 4985: 4972: 4948: 4945: 4925: 4905: 4885: 4865: 4845: 4842: 4839: 4836: 4833: 4813: 4793: 4790: 4770: 4750: 4747: 4738:clearly meets 4727: 4707: 4704: 4684: 4662: 4659: 4656: 4653: 4650: 4630: 4610: 4590: 4570: 4567: 4547: 4544: 4524: 4504: 4501: 4481: 4461: 4458: 4438: 4418: 4415: 4395: 4381: 4374: 4360: 4357: 4354: 4351: 4348: 4328: 4308: 4288: 4268: 4265: 4245: 4242: 4239: 4236: 4213: 4210: 4207: 4204: 4201: 4198: 4178: 4158: 4155: 4152: 4149: 4146: 4143: 4123: 4103: 4100: 4080: 4060: 4040: 4037: 4017: 4003: 3991: 3988: 3985: 3982: 3979: 3976: 3952: 3949: 3946: 3926: 3923: 3920: 3898: 3895: 3892: 3889: 3886: 3883: 3880: 3877: 3874: 3871: 3868: 3865: 3855: 3852: 3849: 3846: 3843: 3840: 3837: 3834: 3831: 3828: 3825: 3822: 3819: 3816: 3813: 3793: 3790: 3787: 3784: 3764: 3761: 3758: 3755: 3744:disjoint union 3731: 3711: 3708: 3705: 3702: 3699: 3685:adherent point 3676: 3673: 3672: 3671: 3659: 3639: 3619: 3599: 3589: 3575: 3572: 3569: 3557: 3556: 3544: 3524: 3504: 3481: 3476: 3472: 3468: 3465: 3462: 3459: 3437: 3433: 3412: 3392: 3389: 3369: 3366: 3363: 3352: 3351: 3340: 3335: 3331: 3327: 3324: 3304: 3292: 3291: 3280: 3275: 3271: 3267: 3264: 3242: 3238: 3234: 3231: 3211: 3191: 3188: 3185: 3182: 3177: 3173: 3169: 3166: 3146: 3143: 3123: 3118: 3114: 3110: 3107: 3087: 3067: 3047: 3044: 3041: 3016: 3011: 3007: 3004: 3001: 2996: 2992: 2987: 2983: 2978: 2974: 2970: 2967: 2944: 2941: 2937: 2933: 2928: 2924: 2903: 2881: 2876: 2873: 2870: 2865: 2860: 2856: 2852: 2847: 2842: 2838: 2825: 2822: 2797: 2794: 2770: 2750: 2747: 2744: 2741: 2738: 2735: 2732: 2710: 2706: 2702: 2699: 2690:there is some 2679: 2676: 2673: 2668: 2664: 2643: 2623: 2611:if, for every 2600: 2561: 2558: 2555: 2535: 2511: 2508: 2505: 2502: 2499: 2479: 2476: 2473: 2470: 2467: 2464: 2461: 2458: 2455: 2452: 2431: 2417: 2397: 2366: 2361: 2357: 2336: 2314: 2310: 2289: 2257: 2237: 2234: 2231: 2226: 2222: 2199: 2195: 2191: 2188: 2179:there is some 2168: 2164: 2160: 2155: 2151: 2130: 2110: 2090: 2087: 2084: 2079: 2075: 2053: 2049: 2046: 2026: 2023: 2003: 1991:if, for every 1978: 1973: 1970: 1967: 1962: 1957: 1953: 1949: 1944: 1939: 1935: 1899: 1896: 1893: 1873: 1870: 1846: 1843: 1831: 1828: 1800: 1780: 1777: 1757: 1754: 1751: 1727: 1707: 1685: 1682: 1656: 1636: 1633: 1609: 1587: 1584: 1556: 1536: 1533: 1513: 1501: 1498: 1486: 1483: 1470:is called the 1459: 1436: 1433: 1409: 1406: 1403: 1400: 1397: 1373: 1353: 1350: 1347: 1315: 1290: 1286: 1265: 1262: 1242: 1222: 1202: 1199: 1196: 1168: 1164: 1142: 1115: 1095: 1075: 1051: 1016: 996: 976: 973: 950: 922: 919: 917: 914: 901: 898: 893: 889: 885: 882: 879: 869: 865: 846: 843: 840: 836: 829: 825: 821: 818: 815: 812: 807: 803: 755: 734: 731: 728: 725: 722: 702: 677: 656: 653: 650: 630: 612:isolated point 599: 579: 559: 539: 515: 505: 491: 467: 440: 437: 434: 429: 425: 404: 384: 381: 361: 341: 321: 295: 291: 288: 284: 278: 274: 270: 235: 232: 212: 192: 172: 152: 128: 108: 88: 65: 26: 9: 6: 4: 3: 2: 7042: 7031: 7028: 7026: 7023: 7021: 7018: 7017: 7015: 7000: 6992: 6988: 6985: 6983: 6980: 6978: 6975: 6974: 6973: 6965: 6963: 6959: 6955: 6953: 6949: 6945: 6943: 6938: 6933: 6931: 6923: 6922: 6919: 6913: 6910: 6908: 6905: 6903: 6900: 6898: 6895: 6893: 6890: 6888: 6885: 6884: 6882: 6880: 6876: 6870: 6869:Orientability 6867: 6865: 6862: 6860: 6857: 6855: 6852: 6850: 6847: 6846: 6844: 6840: 6834: 6831: 6829: 6826: 6824: 6821: 6819: 6816: 6814: 6811: 6809: 6806: 6804: 6801: 6797: 6794: 6792: 6789: 6788: 6787: 6784: 6780: 6777: 6775: 6772: 6770: 6767: 6765: 6762: 6760: 6757: 6756: 6755: 6752: 6750: 6747: 6745: 6742: 6740: 6736: 6733: 6732: 6730: 6726: 6721: 6711: 6708: 6706: 6705:Set-theoretic 6703: 6699: 6696: 6695: 6694: 6691: 6687: 6684: 6683: 6682: 6679: 6677: 6674: 6672: 6669: 6667: 6666:Combinatorial 6664: 6662: 6659: 6657: 6654: 6653: 6651: 6647: 6643: 6636: 6631: 6629: 6624: 6622: 6617: 6616: 6613: 6605: 6601: 6600: 6595: 6591: 6587: 6583: 6579: 6573: 6569: 6565: 6561: 6557: 6553: 6549: 6545: 6541: 6535: 6531: 6527: 6523: 6519: 6515: 6511: 6505: 6501: 6497: 6496: 6491: 6490: 6485: 6481: 6480: 6468: 6463: 6449:on 2021-04-21 6448: 6444: 6438: 6431:. 2021-01-13. 6430: 6424: 6417:. 2021-01-13. 6416: 6410: 6403: 6402:Bourbaki 1989 6398: 6391: 6390:Dugundji 1966 6386: 6382: 6371: 6368: 6365: 6362: 6359: 6356: 6353: 6350: 6347: 6344: 6341: 6338: 6332: 6329: 6323: 6320: 6317: 6314: 6313: 6306: 6293: 6290: 6270: 6250: 6230: 6227: 6204: 6195: 6182: 6169: 6166: 6146: 6140: 6120: 6100: 6097: 6077: 6057: 6037: 6029: 6013: 6003: 5990: 5987: 5967: 5947: 5944: 5941: 5938: 5915: 5889: 5866: 5846: 5833: 5819: 5811: 5795: 5785: 5772: 5769: 5749: 5726: 5703: 5690: 5688: 5682: 5668: 5648: 5645: 5625: 5605: 5602: 5582: 5562: 5559: 5539: 5519: 5516: 5496: 5476: 5456: 5436: 5433: 5413: 5393: 5373: 5353: 5350: 5330: 5310: 5307: 5287: 5267: 5264: 5244: 5224: 5221: 5201: 5181: 5178: 5158: 5138: 5130: 5126: 5113: 5110: 5087: 5081: 5058: 5052: 5049: 5046: 5043: 5040: 5020: 5000: 4992: 4984: 4970: 4960: 4946: 4943: 4923: 4903: 4883: 4863: 4843: 4837: 4831: 4811: 4791: 4788: 4768: 4748: 4745: 4725: 4705: 4702: 4682: 4673: 4660: 4654: 4648: 4628: 4608: 4588: 4568: 4565: 4545: 4542: 4522: 4502: 4499: 4479: 4459: 4456: 4436: 4416: 4413: 4393: 4380: 4378: 4372: 4358: 4352: 4346: 4326: 4306: 4286: 4266: 4263: 4240: 4234: 4224: 4211: 4205: 4196: 4176: 4156: 4150: 4141: 4121: 4101: 4098: 4078: 4058: 4038: 4035: 4015: 4002: 3989: 3983: 3974: 3966: 3950: 3947: 3944: 3924: 3921: 3918: 3909: 3896: 3890: 3884: 3878: 3875: 3869: 3863: 3850: 3844: 3841: 3835: 3829: 3826: 3820: 3814: 3811: 3788: 3782: 3759: 3753: 3745: 3729: 3706: 3700: 3697: 3688: 3686: 3682: 3657: 3637: 3617: 3597: 3587: 3573: 3570: 3567: 3559: 3558: 3542: 3522: 3502: 3494: 3493: 3492: 3479: 3474: 3470: 3466: 3463: 3460: 3457: 3435: 3431: 3410: 3390: 3387: 3367: 3364: 3361: 3338: 3333: 3329: 3325: 3322: 3302: 3294: 3293: 3278: 3273: 3269: 3265: 3262: 3240: 3236: 3232: 3229: 3209: 3186: 3180: 3175: 3171: 3167: 3164: 3144: 3141: 3121: 3116: 3112: 3108: 3105: 3085: 3065: 3045: 3042: 3039: 3031: 3030: 3029: 3014: 3005: 3002: 2999: 2994: 2990: 2985: 2981: 2976: 2972: 2968: 2965: 2958: 2942: 2931: 2926: 2922: 2901: 2874: 2871: 2868: 2863: 2858: 2854: 2850: 2845: 2840: 2836: 2821: 2819: 2815: 2811: 2795: 2792: 2784: 2768: 2748: 2745: 2742: 2736: 2730: 2708: 2704: 2700: 2697: 2677: 2674: 2671: 2666: 2662: 2641: 2621: 2614: 2613:neighbourhood 2598: 2591: 2590: 2581: 2580: 2577:cluster point 2559: 2556: 2553: 2533: 2525: 2506: 2503: 2500: 2477: 2474: 2465: 2462: 2459: 2453: 2450: 2442: 2438: 2433: 2429: 2415: 2395: 2387: 2382: 2380: 2364: 2359: 2355: 2334: 2312: 2308: 2287: 2279: 2275: 2271: 2255: 2235: 2232: 2229: 2224: 2220: 2197: 2193: 2189: 2186: 2166: 2158: 2153: 2149: 2128: 2108: 2088: 2085: 2082: 2077: 2073: 2047: 2044: 2024: 2021: 2001: 1994: 1993:neighbourhood 1971: 1968: 1965: 1960: 1955: 1951: 1947: 1942: 1937: 1933: 1925: 1917: 1914:cluster point 1897: 1894: 1891: 1871: 1868: 1858: 1854: 1849: 1842: 1829: 1826: 1818: 1798: 1778: 1775: 1755: 1752: 1749: 1741: 1725: 1705: 1696: 1683: 1680: 1672: 1671: 1654: 1634: 1631: 1623: 1607: 1598: 1585: 1582: 1574: 1554: 1534: 1531: 1511: 1497: 1484: 1481: 1473: 1457: 1448: 1434: 1431: 1423: 1404: 1395: 1388:of points in 1387: 1371: 1351: 1348: 1345: 1337: 1333: 1332:metric spaces 1329: 1313: 1304: 1288: 1284: 1263: 1260: 1240: 1220: 1200: 1197: 1194: 1186: 1182: 1166: 1162: 1140: 1131: 1127: 1113: 1093: 1073: 1065: 1064:neighbourhood 1049: 1042: 1034: 1033:cluster point 1030: 1014: 994: 974: 971: 964: 948: 936: 932: 927: 899: 891: 887: 880: 877: 867: 864: 861: 844: 841: 838: 834: 827: 819: 816: 810: 805: 801: 792: 787: 783: 781: 777: 773: 768: 729: 726: 723: 700: 692: 651: 628: 620: 615: 613: 597: 577: 557: 537: 529: 513: 504: 500: 499:(also called 498: 493: 489: 487: 483: 479: 475: 471: 466: 463: 460: 458: 454: 438: 435: 432: 427: 423: 402: 382: 379: 359: 339: 319: 312: 289: 286: 276: 272: 261: 257: 253: 252:cluster point 249: 233: 230: 210: 190: 170: 150: 142: 141:neighbourhood 126: 106: 86: 79: 63: 56: 52: 51:cluster point 48: 44: 37: 33: 19: 6999:Publications 6864:Chern number 6854:Betti number 6737: / 6728:Key concepts 6676:Differential 6597: 6559: 6529: 6493: 6488: 6467:Munkres 2000 6462: 6451:. Retrieved 6447:the original 6437: 6423: 6409: 6397: 6385: 6263:is empty or 6187: 6005: 5838: 5787: 5695: 5684: 5128: 5127: 4990: 4989: 4962: 4896:(other than 4674: 4385: 4226: 4007: 3910: 3690:The closure 3689: 3678: 3353: 2955:so that its 2827: 2814:limit points 2584: 2574: 2524:directed set 2434: 2383: 2270:metric space 1919: 1911: 1860: 1848: 1812: 1697: 1668: 1599: 1568: 1503: 1449: 1305: 1185:metric space 1132: 1128: 1036: 1032: 1028: 940: 868:limit points 769: 616: 527: 494: 461: 255: 251: 50: 46: 42: 40: 6962:Wikiversity 6879:Key results 6188:As long as 6006:If a space 4091:other than 3804:; that is, 2430:limit point 1740:cardinality 1472:derived set 1338:are), then 1330:(which all 1183:(such as a 1029:limit point 935:real number 693:. However, 332:is a point 183:other than 99:is a point 43:limit point 7020:Limit sets 7014:Categories 6808:CW complex 6749:Continuity 6739:Closed set 6698:cohomology 6477:References 6453:2021-01-14 5214:is not in 4492:is not in 4373:definition 4227:If we use 3675:Properties 2810:Clustering 2723:such that 2654:and every 2212:such that 2141:and every 2065:such that 1851:See also: 1624:points of 916:Definition 776:closed set 501:points of 415:such that 6987:geometric 6982:algebraic 6833:Cobordism 6769:Hausdorff 6764:connected 6681:Geometric 6671:Continuum 6661:Algebraic 6604:EMS Press 6548:395340485 6486:(1989) . 6377:Citations 6199:∖ 6144:∖ 5942:≠ 5681:is open. 5050:∪ 4200:∖ 4145:∖ 3978:∖ 3948:⊆ 3922:∈ 3894:∅ 3876:∩ 3842:∪ 3815:⁡ 3722:of a set 3701:⁡ 3598:ω 3571:∈ 3503:ω 3475:∙ 3467:⁡ 3436:∙ 3365:⊆ 3334:∙ 3326:⁡ 3303:ω 3274:∙ 3266:⁡ 3241:∙ 3233:⁡ 3176:∙ 3168:⁡ 3117:∙ 3109:⁡ 3043:∈ 3006:∈ 2977:∙ 2969:⁡ 2940:→ 2927:∙ 2880:∞ 2841:∙ 2743:∈ 2701:≥ 2672:∈ 2557:∈ 2507:≤ 2472:→ 2466:≤ 2379:limit set 2360:∙ 2313:∙ 2230:∈ 2190:≥ 2159:∈ 2083:∈ 2048:∈ 1977:∞ 1938:∙ 1895:∈ 1753:∩ 1620:contains 1399:∖ 1349:∈ 1276:In fact, 1198:∈ 1126:itself. 1062:if every 817:− 530:point of 526:contains 433:∈ 290:∈ 248:sequences 7025:Topology 6952:Wikibook 6930:Category 6818:Manifold 6786:Homotopy 6744:Interior 6735:Open set 6693:Homology 6642:Topology 6586:42683260 6560:Topology 6558:(2000). 6530:Topology 6528:(1966). 6518:18588129 6310:See also 6026:has the 5810:discrete 5788:A space 3911:A point 3586:that is 3560:A point 3157:we have 2441:sequence 2280:), then 1884:a point 1386:sequence 1187:), then 1130:point. 987:A point 260:sequence 6977:general 6779:uniform 6759:compact 6710:Digital 6606:, 2001 6498:]. 5960:and so 5532:and so 5131:2: Let 4377:closure 3965:closure 2818:filters 860:has no 503:closure 457:filters 6972:Topics 6774:metric 6649:Fields 6584:  6574:  6546:  6536:  6516:  6506:  5280:Since 4916:), so 4824:is in 4695:is in 4641:is in 4449:is in 3679:Every 2783:subnet 2781:has a 2490:where 1855:, and 1420:whose 484:, the 6754:Space 6492:[ 6185:Proof 5836:Proof 5693:Proof 5129:Proof 4991:Proof 4987:Proof 4383:Proof 4005:Proof 3742:is a 3681:limit 2957:image 2522:is a 2272:or a 2268:is a 1791:then 1647:then 1547:then 1422:limit 1326:is a 1181:space 1153:is a 1027:is a 863:limit 772:limit 689:with 309:in a 258:of a 76:in a 53:of a 49:, or 6582:OCLC 6572:ISBN 6544:OCLC 6534:ISBN 6514:OCLC 6504:ISBN 6030:and 4621:and 4339:and 3495:Any 3202:and 2812:and 2526:and 1334:and 941:Let 778:and 528:some 472:, a 455:and 453:nets 250:. A 34:and 6113:If 5839:If 5808:is 5696:If 5685:No 5489:of 5194:If 4993:1: 4804:If 4761:so 4429:If 4375:of 3967:of 3859:and 3590:an 3588:not 3380:in 2894:in 2634:of 2582:or 2437:net 2381:. 2248:If 2121:of 2014:of 1918:or 1819:of 1742:of 1718:of 1673:of 1575:of 1474:of 1424:is 1306:If 1133:If 1066:of 1035:or 1031:or 1007:in 745:in 701:0.5 667:in 570:of 490:not 459:. 372:of 254:or 143:of 55:set 7016:: 6602:, 6596:, 6580:. 6570:. 6566:: 6542:. 6512:. 4379:. 3812:cl 3698:cl 3687:. 3464:Im 3323:Im 3263:Im 3230:Im 3165:Im 3106:Im 2982::= 2966:Im 2820:. 614:. 45:, 6634:e 6627:t 6620:v 6588:. 6550:. 6520:. 6456:. 6294:. 6291:S 6271:x 6251:S 6231:. 6228:X 6208:} 6205:x 6202:{ 6196:S 6170:. 6167:S 6147:S 6141:X 6121:S 6101:. 6098:S 6078:X 6058:X 6038:S 6014:X 5991:. 5988:X 5968:x 5948:, 5945:x 5939:y 5919:} 5916:x 5913:{ 5893:} 5890:x 5887:{ 5867:X 5847:X 5820:X 5796:X 5773:. 5770:x 5750:x 5730:} 5727:x 5724:{ 5704:x 5669:S 5649:. 5646:S 5626:S 5606:, 5603:S 5583:x 5563:. 5560:S 5540:U 5520:, 5517:S 5497:x 5477:U 5457:x 5437:. 5434:S 5414:x 5394:S 5374:S 5354:. 5351:S 5331:x 5311:, 5308:S 5288:x 5268:. 5265:x 5245:S 5225:, 5222:S 5202:x 5182:. 5179:S 5159:x 5139:S 5114:. 5111:S 5091:) 5088:S 5085:( 5082:L 5062:) 5059:S 5056:( 5053:L 5047:S 5044:= 5041:S 5021:S 5001:S 4971:S 4947:. 4944:S 4924:x 4904:x 4884:S 4864:x 4844:, 4841:) 4838:S 4835:( 4832:L 4812:x 4792:. 4789:S 4769:x 4749:, 4746:S 4726:x 4706:, 4703:S 4683:x 4661:. 4658:) 4655:S 4652:( 4649:L 4629:x 4609:S 4589:x 4569:. 4566:x 4546:, 4543:S 4523:x 4503:, 4500:S 4480:x 4460:, 4457:S 4437:x 4417:. 4414:S 4394:x 4359:. 4356:) 4353:S 4350:( 4347:L 4327:S 4307:S 4287:S 4267:, 4264:S 4244:) 4241:S 4238:( 4235:L 4212:. 4209:} 4206:x 4203:{ 4197:S 4177:x 4157:, 4154:} 4151:x 4148:{ 4142:S 4122:x 4102:, 4099:x 4079:S 4059:x 4039:, 4036:S 4016:x 3990:. 3987:} 3984:x 3981:{ 3975:S 3951:X 3945:S 3925:X 3919:x 3897:. 3891:= 3888:) 3885:S 3882:( 3879:I 3873:) 3870:S 3867:( 3864:L 3854:) 3851:S 3848:( 3845:I 3839:) 3836:S 3833:( 3830:L 3827:= 3824:) 3821:S 3818:( 3792:) 3789:S 3786:( 3783:I 3763:) 3760:S 3757:( 3754:L 3730:S 3710:) 3707:S 3704:( 3658:A 3638:x 3618:A 3574:X 3568:x 3543:A 3523:A 3480:. 3471:x 3461:= 3458:A 3432:x 3411:A 3391:, 3388:X 3368:X 3362:A 3339:. 3330:x 3279:. 3270:x 3237:x 3210:x 3190:} 3187:x 3184:{ 3181:= 3172:x 3145:, 3142:x 3122:. 3113:x 3086:x 3066:x 3046:X 3040:x 3015:} 3010:N 3003:n 3000:: 2995:n 2991:x 2986:{ 2973:x 2943:X 2936:N 2932:: 2923:x 2902:X 2875:1 2872:= 2869:n 2864:) 2859:n 2855:x 2851:( 2846:= 2837:x 2796:. 2793:x 2769:f 2749:, 2746:V 2740:) 2737:p 2734:( 2731:f 2709:0 2705:p 2698:p 2678:, 2675:P 2667:0 2663:p 2642:x 2622:V 2599:f 2560:X 2554:x 2534:X 2510:) 2504:, 2501:P 2498:( 2478:, 2475:X 2469:) 2463:, 2460:P 2457:( 2454:: 2451:f 2416:x 2396:x 2365:. 2356:x 2335:x 2309:x 2288:x 2256:X 2236:. 2233:V 2225:n 2221:x 2198:0 2194:n 2187:n 2167:, 2163:N 2154:0 2150:n 2129:x 2109:V 2089:. 2086:V 2078:n 2074:x 2052:N 2045:n 2025:, 2022:x 2002:V 1972:1 1969:= 1966:n 1961:) 1956:n 1952:x 1948:( 1943:= 1934:x 1898:X 1892:x 1872:, 1869:X 1830:. 1827:S 1799:x 1779:, 1776:S 1756:S 1750:U 1726:x 1706:U 1684:. 1681:S 1655:x 1635:, 1632:S 1608:x 1586:. 1583:S 1555:x 1535:, 1532:S 1512:x 1485:. 1482:S 1458:S 1435:. 1432:x 1408:} 1405:x 1402:{ 1396:S 1372:S 1352:X 1346:x 1314:X 1289:1 1285:T 1264:. 1261:S 1241:x 1221:S 1201:X 1195:x 1167:1 1163:T 1141:X 1114:x 1094:S 1074:x 1050:S 1015:X 995:x 975:. 972:X 949:S 900:. 897:} 892:n 888:x 884:{ 881:= 878:S 845:1 842:+ 839:n 835:n 828:n 824:) 820:1 814:( 811:= 806:n 802:x 754:R 733:] 730:1 727:, 724:0 721:[ 676:R 655:} 652:0 649:{ 629:0 598:x 578:S 558:x 538:S 514:x 439:. 436:V 428:n 424:x 403:n 383:, 380:x 360:V 340:x 320:X 294:N 287:n 283:) 277:n 273:x 269:( 234:. 231:S 211:S 191:x 171:S 151:x 127:S 107:x 87:X 64:S 38:. 20:)

Index

Limit point of a set
Limit (mathematics)
Limit (disambiguation) § Mathematics
set
topological space
neighbourhood
sequences
sequence
topological space
nets
filters
limit point of a sequence
limit point of a filter
limit point of a net
sequence converges to
filter converges to
net converges to
adherent points
closure
isolated point
boundary points
standard topology
limit
closed set
topological closure

Euclidean topology
limit

rational numbers

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