Knowledge

Set-builder notation

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There is no order among the elements of a set (this explains and validates the equality of the last example), but with the ellipses notation, we use an ordered sequence before (or after) the ellipsis as a convenient notational vehicle for explaining which elements are in a set. The first few elements
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is clear from context, it may be not explicitly specified. It is common in the literature for an author to state the domain ahead of time, and then not specify it in the set-builder notation. For example, an author may say something such as, "Unless otherwise stated, variables are to be taken to be
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In each preceding example, each set is described by enumerating its elements. Not all sets can be described in this way, or if they can, their enumeration may be too long or too complicated to be useful. Therefore, many sets are defined by a property that characterizes their elements. This
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of the sequence are shown, then the ellipses indicate that the simplest interpretation should be applied for continuing the sequence. Should no terminating value appear to the right of the ellipses, then the sequence is considered to be unbounded.
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The following examples illustrate particular sets defined by set-builder notation via predicates. In each case, the domain is specified on the left side of the vertical bar, while the rule is specified on the right side.
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However, the prose approach may lack accuracy or be ambiguous. Thus, set-builder notation is often used with a predicate characterizing the elements of the set being defined, as described in the following section.
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Two sets are equal if and only if they have the same elements. Sets defined by set builder notation are equal if and only if their set builder rules, including the domain specifiers, are equivalent. That is
4449: 4291:, and set objects, respectively. Python uses an English-based syntax. Haskell replaces the set-builder's braces with square brackets and uses symbols, including the standard set-builder vertical bar. 3076: 1588: 78: 3568: 2587: 2425: 4143: 3237: 1933: 1744: 2342: 1845: 3290: 3174: 1465: 2986: 2202: 1224: 4199: 1512: 2823: 828: 347: 1676: 3678:
Therefore, in order to prove the equality of two sets defined by set builder notation, it suffices to prove the equivalence of their predicates, including the domain qualifiers.
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separator, and a predicate. Thus there is a variable on the left of the separator, and a rule on the right of it. These three parts are contained in curly brackets:
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When inverse functions can be explicitly stated, the expression on the left can be eliminated through simple substitution. Consider the example set
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using Sequence Comprehensions, where the "for" keyword returns a list of the yielded variables using the "yield" keyword.
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natural numbers," though in less formal contexts where the domain can be assumed, a written mention is often unnecessary.
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can be described directly by enumerating all of its elements between curly brackets, as in the following two examples:
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although seemingly well formed as a set builder expression, cannot define a set without producing a contradiction.
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In Python, the set-builder's braces are replaced with square brackets, parentheses, or curly braces, giving list,
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The set builder notation and list comprehension notation are both instances of a more general notation known as
2141: 5934: 5082: 4671: 4549: 4236: 4224: 950: 1179: 5548: 5427: 4968: 4455: 4220: 4157: 1470: 2775: 1326:{\displaystyle \{x\mid x\in E{\text{ and }}\Phi (x)\}\quad {\text{or}}\quad \{x\mid x\in E\land \Phi (x)\}.} 781: 5791: 4987: 4568: 4295: 4288: 302: 1632: 5784: 5422: 5385: 5248: 4232: 214: 2734: 1101: 975: 2459: 354: 5439: 4322: 2589:
is a notational variant for the same set of even natural numbers. It is not necessary to specify that
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for which the predicate is true. This can easily lead to contradictions and paradoxes. For example,
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creates a set of pairs, where each pair puts an integer into correspondence with an odd integer.
2697:{\displaystyle \{a\in \mathbb {R} \mid (\exists p\in \mathbb {Z} )(\exists q\in \mathbb {Z} )\}} 761: 5845: 5726: 5538: 5358: 5098: 4260: 4011: 3876:{\displaystyle (x\in \mathbb {R} \land x^{2}=1)\Leftrightarrow (x\in \mathbb {Q} \land |x|=1).} 3330: 2303: 5119: 3966: 1850: 1383: 5761: 5731: 5675: 5595: 5575: 5553: 4216: 3893: 116: 5197: 3295: 2437: 1593: 1343: 5835: 5825: 5659: 5543: 5483: 5370: 4010:, set builder notation is not part of the formal syntax of the theory. Instead, there is a 3930: 1626: 833: 893:
characterization may be done informally using general prose, as in the following example.
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for which the predicate holds (is true) belong to the set being defined. All values of
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When it is desired to denote a set that contains elements from a regular sequence, an
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obtained from this axiom is exactly the set described in set builder notation as
3772:{\displaystyle \{x\in \mathbb {R} \mid x^{2}=1\}=\{x\in \mathbb {Q} \mid |x|=1\}} 3471:{\displaystyle \{2t+1\mid t\in \mathbb {Z} \}=\{u\mid (u-1)/2\in \mathbb {Z} \}.} 2705: 1747: 2931:{\displaystyle \{f(x)\mid \Phi (x)\}=\{y\mid \exists x(y=f(x)\wedge \Phi (x))\}} 5903: 5700: 5681: 5585: 5570: 5527: 5463: 5405: 2431: 2280:{\displaystyle \{(x,y)\in \mathbb {R} \times \mathbb {R} \mid 0<y<f(x)\}} 1337: 396: 5923: 5908: 5710: 5624: 5619: 2042:{\displaystyle G_{m}=\{x\in \mathbb {Z} \mid x\geq m\}=\{m,m+1,m+2,\ldots \}} 961:
otherwise. In this form, set-builder notation has three parts: a variable, a
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Consider these set-builder notation examples in some programming languages:
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is the set of all natural numbers, is the set of all even natural numbers.
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is the set containing the four numbers 3, 7, 15, and 31, and nothing else.
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Set-builder notation can be used to describe a set that is defined by a
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In general, it is not a good idea to consider sets without defining a
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for which the predicate does not hold do not belong to the set. Thus
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is a natural number, as this is implied by the formula on the right.
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This is sometimes called the "roster method" for specifying a set.
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An extension of set-builder notation replaces the single variable
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is a formula in the language of set theory, then there is a set
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The vertical bar (or colon) is a separator that can be read as "
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Richard Aufmann, Vernon C. Barker, and Joanne Lockwood, 2007,
5563: 5330: 5266: 5124:(6th ed.). New York, NY: McGraw-Hill. pp. 111–112. 100: 4444:{\displaystyle \{(k,x)\ |\ k\in K\wedge x\in X\wedge P(x)\}} 1936: 1070:", "for which", or "with the property that". The formula 127:, or stating the properties that its members must satisfy. 3782:
because the two rule predicates are logically equivalent:
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More complex expressions on the left side of the notation
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notation may be employed, as shown in the next examples:
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Irvine, Andrew David; Deutsch, Harry (9 October 2016) .
3071:{\displaystyle \{p/q\mid p,q\in \mathbb {Z} ,q\not =0\}} 1583:{\displaystyle \{x\in E\mid \Phi _{1}(x),\Phi _{2}(x)\}} 73:{\displaystyle \{n\mid \exists k\in \mathbb {Z} ,n=2k\}} 3563:{\displaystyle \{x\in A\mid P(x)\}=\{x\in B\mid Q(x)\}} 4372: 4325: 4160: 4053: 3969: 3933: 3896: 3791: 3690: 3582: 3496: 3386: 3333: 3298: 3249: 3184: 3133: 3106: 3084: 3018: 2994: 2951: 2834: 2778: 2737: 2603: 2582:{\displaystyle \{n\mid (\exists k\in \mathbb {N} )\}} 2528: 2468: 2440: 2420:{\displaystyle \{n\in \mathbb {N} \mid (\exists k)\}} 2352: 2320: 2212: 2144: 2055: 1954: 1888: 1853: 1797: 1763: 1706: 1635: 1596: 1520: 1473: 1415: 1386: 1346: 1238: 1182: 1104: 1025: 978: 922: 902: 863: 836: 784: 764: 711: 685: 659: 621: 589: 569: 531: 407: 357: 305: 217: 171: 28: 5081:, which permits map/filter-like operations over any 3886:
This equivalence holds because, for any real number
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symbol denotes the logical "and" operator, known as
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is the set of integers between 1 and 100 inclusive.
4443: 4357: 4193: 4138:{\displaystyle (\forall E)(\exists Y)(\forall x).} 4137: 3990: 3955: 3915: 3875: 3771: 3666: 3562: 3470: 3365: 3319: 3284: 3232:{\displaystyle \{(t,2t+1)\mid t\in \mathbb {Z} \}} 3231: 3168: 3117: 3092: 3070: 3002: 2980: 2930: 2817: 2764: 2696: 2581: 2495: 2446: 2419: 2336: 2279: 2196: 2130: 2041: 1927: 1874: 1839: 1781: 1738: 1670: 1602: 1582: 1506: 1459: 1401: 1352: 1325: 1218: 1131: 1055: 1005: 928: 908: 881: 849: 822: 770: 747: 697: 671: 645: 607: 575: 555: 509: 387: 341: 265: 201: 72: 4259:It has been suggested that parts of this page be 2344:denotes the set of ordered pairs of real numbers. 1928:{\displaystyle \{x\in \mathbb {R} \mid x^{2}=1\}} 5921: 3963:. In particular, both sets are equal to the set 1739:{\displaystyle \{x\in \mathbb {R} \mid x>0\}} 2337:{\displaystyle \mathbb {R} \times \mathbb {R} } 1840:{\displaystyle \{x\in \mathbb {R} \mid |x|=1\}} 953:, that is, a logical formula that evaluates to 3285:{\displaystyle \{2t+1\mid t\in \mathbb {Z} \}} 3169:{\displaystyle \{2t+1\mid t\in \mathbb {Z} \}} 2287:is the set of pairs of real numbers such that 1460:{\displaystyle \Phi _{1}(x)\land \Phi _{2}(x)} 944: 147: 5282: 5221: 1173:can appear on the left of the vertical bar: 130:Defining sets by properties is also known as 4438: 4373: 4352: 4326: 4215:A similar notation available in a number of 4188: 4161: 3985: 3970: 3766: 3730: 3724: 3691: 3557: 3530: 3524: 3497: 3462: 3422: 3416: 3387: 3279: 3250: 3226: 3185: 3163: 3134: 3065: 3019: 2981:{\displaystyle \{2n\mid n\in \mathbb {N} \}} 2975: 2952: 2925: 2871: 2865: 2835: 2809: 2779: 2759: 2738: 2691: 2604: 2576: 2529: 2414: 2353: 2274: 2213: 2191: 2161: 2125: 2101: 2095: 2069: 2036: 2000: 1994: 1968: 1922: 1889: 1869: 1854: 1834: 1798: 1733: 1707: 1662: 1636: 1577: 1521: 1501: 1474: 1317: 1284: 1274: 1239: 1210: 1183: 1126: 1105: 1047: 1026: 1000: 979: 923: 903: 817: 785: 742: 724: 640: 622: 550: 532: 504: 462: 456: 408: 382: 358: 336: 306: 260: 242: 236: 218: 196: 172: 67: 29: 4204: 936:is the set of all addresses on Pine Street. 5289: 5275: 4034:whose members are exactly the elements of 2197:{\displaystyle G_{-2}=\{-2,-1,0,\ldots \}} 5121:Discrete Mathematics and its Applications 3841: 3802: 3740: 3701: 3458: 3412: 3275: 3222: 3159: 3108: 3086: 3049: 2996: 2971: 2654: 2634: 2614: 2551: 2454:sign stands for "and", which is known as 2392: 2363: 2330: 2322: 2243: 2235: 2079: 1978: 1899: 1808: 1717: 48: 1377: 1219:{\displaystyle \{x\in E\mid \Phi (x)\},} 1162: 154:Set (mathematics) § Roster notation 5159:A Transition to Mathematics with Proofs 4194:{\displaystyle \{x\in E\mid \Phi (x)\}} 1507:{\displaystyle \{x\in E\mid \Phi (x)\}} 563:denotes the set of all natural numbers 5922: 5161:, Jones & Bartlett, pp. 44ff. 5146:Intermediate Algebra with Applications 4001: 3482:Equivalent predicates yield equal sets 2818:{\displaystyle \{f(x)\mid \Phi (x)\},} 1937:equivalent predicates yield equal sets 1590:, using a comma instead of the symbol 1376:for which the predicate is true (see " 823:{\displaystyle \{a_{1},\dots ,a_{n}\}} 5270: 5170: 5117: 4006:In many formal set theories, such as 3377:in the set builder notation to find 1229:or by adjoining it to the predicate: 342:{\displaystyle \{1,2,3,\ldots ,100\}} 4245: 1671:{\displaystyle \{x~|~x\not \in x\},} 5228:Stanford Encyclopedia of Philosophy 266:{\displaystyle \{a,c,b\}=\{a,b,c\}} 13: 4176: 4117: 4081: 4069: 4057: 3586: 2910: 2880: 2853: 2797: 2765:{\displaystyle \{x\mid \Phi (x)\}} 2747: 2644: 2624: 2541: 2472: 2373: 1882:. This set can also be defined as 1773: 1623:all possible things that may exist 1559: 1537: 1489: 1439: 1417: 1387: 1305: 1262: 1198: 1132:{\displaystyle \{x\mid \Phi (x)\}} 1114: 1035: 1006:{\displaystyle \{x\mid \Phi (x)\}} 988: 765: 90:expressed in set-builder notation. 38: 14: 5946: 388:{\displaystyle \{1,2,3,\ldots \}} 16:Use of braces for specifying sets 5320: 4358:{\displaystyle \{l\ |\ l\in L\}} 4250: 3125:the set of all rational numbers. 2291:is greater than 0 and less than 1336:The ∈ symbol here denotes 3100:is the set of all integers, is 2496:{\displaystyle (\exists x)P(x)} 1283: 1277: 1056:{\displaystyle \{x:\Phi (x)\}.} 957:for an element of the set, and 748:{\displaystyle =\{1,\dots ,0\}} 5296: 5241: 5215: 5190: 5164: 5151: 5138: 5111: 4435: 4429: 4395: 4388: 4376: 4336: 4185: 4179: 4129: 4126: 4120: 4102: 4090: 4087: 4078: 4075: 4066: 4063: 4054: 3943: 3935: 3867: 3857: 3849: 3831: 3828: 3825: 3792: 3756: 3748: 3661: 3658: 3655: 3649: 3631: 3628: 3625: 3622: 3616: 3598: 3595: 3592: 3583: 3554: 3548: 3521: 3515: 3443: 3431: 3352: 3340: 3209: 3188: 2922: 2919: 2913: 2904: 2898: 2886: 2862: 2856: 2847: 2841: 2806: 2800: 2791: 2785: 2756: 2750: 2688: 2661: 2658: 2641: 2638: 2621: 2573: 2558: 2555: 2538: 2490: 2484: 2478: 2469: 2411: 2382: 2379: 2370: 2271: 2265: 2228: 2216: 1824: 1816: 1776: 1764: 1646: 1617:, as this would represent the 1574: 1568: 1552: 1546: 1498: 1492: 1454: 1448: 1432: 1426: 1396: 1390: 1370:that belong to some given set 1314: 1308: 1271: 1265: 1207: 1201: 1123: 1117: 1044: 1038: 997: 991: 718: 712: 666: 660: 646:{\displaystyle \{1,\dots ,n\}} 556:{\displaystyle \{1,\dots ,n\}} 1: 3118:{\displaystyle \mathbb {Q} ,} 2503:is read as "there exists an 882:{\displaystyle 1\leq i\leq n} 608:{\displaystyle 1\leq i\leq n} 202:{\displaystyle \{7,3,15,31\}} 4294:The same can be achieved in 4239:operations over one or more 3093:{\displaystyle \mathbb {Z} } 3003:{\displaystyle \mathbb {N} } 1139:is the set of all values of 7: 5092: 4008:Zermelo–Fraenkel set theory 3667:{\displaystyle (\forall t)} 3176:is the set of odd integers. 1782:{\displaystyle (0,\infty )} 1746:is the set of all strictly 1691: 945:Sets defined by a predicate 679:. A subtle special case is 517:is the set of all integers. 148:Sets defined by enumeration 10: 5951: 5780:von Neumann–Bernays–Gödel 5157:Michael J Cullinan, 2012, 4208: 4012:set existence axiom scheme 3927:is a rational number with 2460:existential quantification 1753:, which can be written in 1629:shows that the expression 771:{\displaystyle \emptyset } 151: 5844: 5807: 5719: 5609: 5581:One-to-one correspondence 5497: 5438: 5329: 5318: 5304: 5249:"Sequence Comprehensions" 5148:, Brooks Cole, p. 6. 4834: 4764: 4670: 4567: 4548: 4454: 3366:{\displaystyle t=(u-1)/2} 1145:that satisfy the formula 916:addresses on Pine Street 5104: 5038: 5011: 4998: 4992: 4979: 4973: 4882: 4840: 4788: 4770: 4700: 4676: 4603: 4573: 4560: 4554: 4487: 4460: 4205:In programming languages 3991:{\displaystyle \{-1,1\}} 3292:. Make the substitution 1875:{\displaystyle \{-1,1\}} 1402:{\displaystyle \Phi (x)} 653:is the bracket notation 99:and its applications to 5118:Rosen, Kenneth (2007). 4014:, which states that if 3916:{\displaystyle x^{2}=1} 1681:In cases where the set 1159:satisfies the formula. 830:denotes the set of all 615:. Another notation for 138:or as defining a set's 5539:Constructible universe 5366:Constructibility (V=L) 5198:"Set-Builder Notation" 5099:Glossary of set theory 4445: 4359: 4195: 4139: 3992: 3957: 3917: 3877: 3773: 3668: 3564: 3472: 3367: 3321: 3320:{\displaystyle u=2t+1} 3286: 3233: 3170: 3119: 3094: 3072: 3004: 2982: 2932: 2819: 2766: 2698: 2583: 2497: 2448: 2447:{\displaystyle \land } 2421: 2338: 2281: 2198: 2132: 2043: 1929: 1876: 1841: 1783: 1740: 1672: 1604: 1603:{\displaystyle \land } 1584: 1508: 1461: 1403: 1354: 1353:{\displaystyle \land } 1327: 1220: 1133: 1057: 1007: 930: 910: 883: 851: 824: 772: 749: 699: 673: 647: 609: 577: 557: 511: 389: 343: 273:is the set containing 267: 203: 81: 74: 5935:Mathematical notation 5762:Principia Mathematica 5596:Transfinite induction 5455:(i.e. set difference) 5177:mathworld.wolfram.com 4446: 4360: 4217:programming languages 4196: 4140: 3993: 3958: 3956:{\displaystyle |x|=1} 3918: 3878: 3774: 3669: 3565: 3473: 3368: 3322: 3287: 3234: 3171: 3120: 3095: 3073: 3005: 2983: 2933: 2825:which should be read 2820: 2767: 2699: 2584: 2498: 2449: 2422: 2339: 2282: 2199: 2133: 2044: 1930: 1877: 1842: 1784: 1741: 1673: 1605: 1585: 1514:is sometimes written 1509: 1462: 1404: 1355: 1328: 1221: 1163:Specifying the domain 1134: 1058: 1008: 931: 911: 884: 852: 850:{\displaystyle a_{i}} 825: 773: 750: 700: 674: 648: 610: 578: 558: 512: 390: 344: 268: 204: 117:mathematical notation 75: 21: 5836:Burali-Forti paradox 5591:Set-builder notation 5544:Continuum hypothesis 5484:Symmetric difference 5079:monad comprehensions 4370: 4323: 4158: 4051: 3967: 3931: 3894: 3789: 3688: 3580: 3494: 3384: 3331: 3296: 3247: 3182: 3131: 3104: 3082: 3016: 2992: 2949: 2832: 2776: 2735: 2601: 2526: 2466: 2438: 2350: 2318: 2210: 2142: 2053: 1952: 1886: 1851: 1795: 1761: 1704: 1633: 1594: 1518: 1471: 1413: 1384: 1344: 1236: 1180: 1102: 1023: 976: 920: 900: 861: 834: 782: 762: 709: 683: 657: 619: 587: 567: 529: 405: 355: 303: 215: 169: 113:set-builder notation 26: 5797:Tarski–Grothendieck 5224:"Russell's Paradox" 5171:Weisstein, Eric W. 4002:Set existence axiom 2456:logical conjunction 1615:domain of discourse 1378:Set existence axiom 1362:logical conjunction 698:{\displaystyle n=0} 123:by enumerating its 5386:Limitation of size 4441: 4355: 4265:List comprehension 4229:list comprehension 4211:List comprehension 4191: 4135: 3988: 3953: 3913: 3873: 3769: 3664: 3560: 3468: 3363: 3327:, which is to say 3317: 3282: 3229: 3166: 3115: 3090: 3068: 3000: 2978: 2928: 2815: 2762: 2694: 2579: 2493: 2462:. So for example, 2444: 2427:is the set of all 2417: 2334: 2277: 2194: 2128: 2039: 1925: 1872: 1837: 1779: 1736: 1668: 1600: 1580: 1504: 1457: 1399: 1350: 1323: 1216: 1129: 1078:is said to be the 1053: 1003: 929:{\displaystyle \}} 926: 909:{\displaystyle \{} 906: 879: 847: 820: 768: 745: 695: 669: 643: 605: 573: 553: 507: 385: 339: 263: 199: 70: 5917: 5916: 5826:Russell's paradox 5775:Zermelo–Fraenkel 5676:Dedekind-infinite 5549:Diagonal argument 5448:Cartesian product 5312:Set (mathematics) 5131:978-0-07-288008-3 5075: 5074: 4401: 4393: 4342: 4334: 4285: 4284: 4231:, which combines 2731:. So instead of 2313:cartesian product 2049:. As an example, 1942:For each integer 1755:interval notation 1652: 1644: 1627:Russell's paradox 1409:is a conjunction 1281: 1260: 1153:, if no value of 576:{\displaystyle i} 132:set comprehension 119:for describing a 5942: 5899:Bertrand Russell 5889:John von Neumann 5874:Abraham Fraenkel 5869:Richard Dedekind 5831:Suslin's problem 5742:Cantor's theorem 5459:De Morgan's laws 5324: 5291: 5284: 5277: 5268: 5267: 5261: 5260: 5258: 5256: 5245: 5239: 5238: 5236: 5234: 5219: 5213: 5212: 5210: 5208: 5194: 5188: 5187: 5185: 5183: 5168: 5162: 5155: 5149: 5142: 5136: 5135: 5115: 5069: 5066: 5063: 5060: 5057: 5054: 5051: 5048: 5045: 5042: 5033: 5030: 5027: 5024: 5021: 5018: 5015: 4961: 4958: 4955: 4952: 4949: 4946: 4943: 4940: 4937: 4934: 4931: 4928: 4925: 4922: 4919: 4916: 4913: 4910: 4907: 4904: 4901: 4898: 4895: 4892: 4889: 4886: 4877: 4874: 4871: 4868: 4865: 4862: 4859: 4856: 4853: 4850: 4847: 4844: 4828: 4825: 4822: 4819: 4816: 4813: 4810: 4807: 4804: 4801: 4798: 4795: 4792: 4783: 4780: 4777: 4774: 4758: 4755: 4752: 4749: 4746: 4743: 4740: 4737: 4734: 4731: 4728: 4725: 4722: 4719: 4716: 4713: 4710: 4707: 4704: 4695: 4692: 4689: 4686: 4683: 4680: 4664: 4661: 4658: 4655: 4652: 4649: 4646: 4643: 4640: 4637: 4634: 4631: 4628: 4625: 4622: 4619: 4616: 4613: 4610: 4607: 4598: 4595: 4592: 4589: 4586: 4583: 4580: 4577: 4542: 4539: 4536: 4533: 4530: 4527: 4524: 4521: 4518: 4515: 4512: 4509: 4506: 4503: 4500: 4497: 4494: 4491: 4482: 4479: 4476: 4473: 4470: 4467: 4464: 4450: 4448: 4447: 4442: 4399: 4398: 4391: 4364: 4362: 4361: 4356: 4340: 4339: 4332: 4304: 4303: 4280: 4277: 4254: 4253: 4246: 4200: 4198: 4197: 4192: 4153: 4144: 4142: 4141: 4136: 4043: 4039: 4033: 4027: 4019: 3997: 3995: 3994: 3989: 3962: 3960: 3959: 3954: 3946: 3938: 3922: 3920: 3919: 3914: 3906: 3905: 3882: 3880: 3879: 3874: 3860: 3852: 3844: 3818: 3817: 3805: 3778: 3776: 3775: 3770: 3759: 3751: 3743: 3717: 3716: 3704: 3673: 3671: 3670: 3665: 3573:if and only if 3569: 3567: 3566: 3561: 3477: 3475: 3474: 3469: 3461: 3450: 3415: 3372: 3370: 3369: 3364: 3359: 3326: 3324: 3323: 3318: 3291: 3289: 3288: 3283: 3278: 3238: 3236: 3235: 3230: 3225: 3175: 3173: 3172: 3167: 3162: 3124: 3122: 3121: 3116: 3111: 3099: 3097: 3096: 3091: 3089: 3077: 3075: 3074: 3069: 3052: 3029: 3009: 3007: 3006: 3001: 2999: 2987: 2985: 2984: 2979: 2974: 2937: 2935: 2934: 2929: 2824: 2822: 2821: 2816: 2771: 2769: 2768: 2763: 2726: 2706:rational numbers 2703: 2701: 2700: 2695: 2657: 2637: 2617: 2594: 2588: 2586: 2585: 2580: 2554: 2519: 2508: 2502: 2500: 2499: 2494: 2453: 2451: 2450: 2445: 2426: 2424: 2423: 2418: 2395: 2366: 2343: 2341: 2340: 2335: 2333: 2325: 2310: 2301: 2286: 2284: 2283: 2278: 2246: 2238: 2203: 2201: 2200: 2195: 2157: 2156: 2137: 2135: 2134: 2129: 2082: 2065: 2064: 2048: 2046: 2045: 2040: 1981: 1964: 1963: 1948:, we can define 1947: 1934: 1932: 1931: 1926: 1915: 1914: 1902: 1881: 1879: 1878: 1873: 1846: 1844: 1843: 1838: 1827: 1819: 1811: 1788: 1786: 1785: 1780: 1745: 1743: 1742: 1737: 1720: 1686: 1677: 1675: 1674: 1669: 1650: 1649: 1642: 1609: 1607: 1606: 1601: 1589: 1587: 1586: 1581: 1567: 1566: 1545: 1544: 1513: 1511: 1510: 1505: 1466: 1464: 1463: 1458: 1447: 1446: 1425: 1424: 1408: 1406: 1405: 1400: 1375: 1369: 1359: 1357: 1356: 1351: 1332: 1330: 1329: 1324: 1282: 1279: 1261: 1258: 1225: 1223: 1222: 1217: 1172: 1158: 1149:. It may be the 1148: 1144: 1138: 1136: 1135: 1130: 1097: 1091: 1086:. All values of 1077: 1062: 1060: 1059: 1054: 1012: 1010: 1009: 1004: 935: 933: 932: 927: 915: 913: 912: 907: 888: 886: 885: 880: 856: 854: 853: 848: 846: 845: 829: 827: 826: 821: 816: 815: 797: 796: 777: 775: 774: 769: 755:is equal to the 754: 752: 751: 746: 704: 702: 701: 696: 678: 676: 675: 672:{\displaystyle } 670: 652: 650: 649: 644: 614: 612: 611: 606: 582: 580: 579: 574: 562: 560: 559: 554: 516: 514: 513: 508: 394: 392: 391: 386: 348: 346: 345: 340: 284: 280: 276: 272: 270: 269: 264: 208: 206: 205: 200: 109:computer science 91: 79: 77: 76: 71: 51: 5950: 5949: 5945: 5944: 5943: 5941: 5940: 5939: 5920: 5919: 5918: 5913: 5840: 5819: 5803: 5768:New Foundations 5715: 5605: 5524:Cardinal number 5507: 5493: 5434: 5325: 5316: 5300: 5295: 5265: 5264: 5254: 5252: 5247: 5246: 5242: 5232: 5230: 5220: 5216: 5206: 5204: 5196: 5195: 5191: 5181: 5179: 5169: 5165: 5156: 5152: 5143: 5139: 5132: 5116: 5112: 5107: 5095: 5071: 5070: 5067: 5064: 5061: 5058: 5055: 5052: 5049: 5046: 5043: 5040: 5035: 5034: 5031: 5028: 5025: 5022: 5019: 5016: 5013: 5001: 5000: 4995: 4994: 4982: 4981: 4976: 4975: 4963: 4962: 4959: 4956: 4953: 4950: 4947: 4944: 4941: 4938: 4935: 4932: 4929: 4926: 4923: 4920: 4917: 4914: 4911: 4908: 4905: 4902: 4899: 4896: 4893: 4890: 4887: 4884: 4879: 4878: 4875: 4872: 4869: 4866: 4863: 4860: 4857: 4854: 4851: 4848: 4845: 4842: 4830: 4829: 4826: 4823: 4820: 4817: 4814: 4811: 4808: 4805: 4802: 4799: 4796: 4793: 4790: 4785: 4784: 4781: 4778: 4775: 4772: 4760: 4759: 4756: 4753: 4750: 4747: 4744: 4741: 4738: 4735: 4732: 4729: 4726: 4723: 4720: 4717: 4714: 4711: 4708: 4705: 4702: 4697: 4696: 4693: 4690: 4687: 4684: 4681: 4678: 4666: 4665: 4662: 4659: 4656: 4653: 4650: 4647: 4644: 4641: 4638: 4635: 4632: 4629: 4626: 4623: 4620: 4617: 4614: 4611: 4608: 4605: 4600: 4599: 4596: 4593: 4590: 4587: 4584: 4581: 4578: 4575: 4563: 4562: 4557: 4556: 4544: 4543: 4540: 4537: 4534: 4531: 4528: 4525: 4522: 4519: 4516: 4513: 4510: 4507: 4504: 4501: 4498: 4495: 4492: 4489: 4484: 4483: 4480: 4477: 4474: 4471: 4468: 4465: 4462: 4394: 4371: 4368: 4367: 4335: 4324: 4321: 4320: 4281: 4275: 4272: 4255: 4251: 4213: 4207: 4159: 4156: 4155: 4149: 4052: 4049: 4048: 4041: 4035: 4029: 4021: 4015: 4004: 3968: 3965: 3964: 3942: 3934: 3932: 3929: 3928: 3923:if and only if 3901: 3897: 3895: 3892: 3891: 3856: 3848: 3840: 3813: 3809: 3801: 3790: 3787: 3786: 3755: 3747: 3739: 3712: 3708: 3700: 3689: 3686: 3685: 3581: 3578: 3577: 3495: 3492: 3491: 3484: 3457: 3446: 3411: 3385: 3382: 3381: 3373:, then replace 3355: 3332: 3329: 3328: 3297: 3294: 3293: 3274: 3248: 3245: 3244: 3221: 3183: 3180: 3179: 3158: 3132: 3129: 3128: 3107: 3105: 3102: 3101: 3085: 3083: 3080: 3079: 3048: 3025: 3017: 3014: 3013: 2995: 2993: 2990: 2989: 2970: 2950: 2947: 2946: 2833: 2830: 2829: 2777: 2774: 2773: 2736: 2733: 2732: 2722: 2719: 2653: 2633: 2613: 2602: 2599: 2598: 2590: 2550: 2527: 2524: 2523: 2510: 2504: 2467: 2464: 2463: 2439: 2436: 2435: 2432:natural numbers 2391: 2362: 2351: 2348: 2347: 2329: 2321: 2319: 2316: 2315: 2306: 2292: 2242: 2234: 2211: 2208: 2207: 2149: 2145: 2143: 2140: 2139: 2078: 2060: 2056: 2054: 2051: 2050: 1977: 1959: 1955: 1953: 1950: 1949: 1943: 1910: 1906: 1898: 1887: 1884: 1883: 1852: 1849: 1848: 1823: 1815: 1807: 1796: 1793: 1792: 1762: 1759: 1758: 1716: 1705: 1702: 1701: 1694: 1682: 1645: 1634: 1631: 1630: 1595: 1592: 1591: 1562: 1558: 1540: 1536: 1519: 1516: 1515: 1472: 1469: 1468: 1442: 1438: 1420: 1416: 1414: 1411: 1410: 1385: 1382: 1381: 1371: 1365: 1345: 1342: 1341: 1278: 1259: and  1257: 1237: 1234: 1233: 1181: 1178: 1177: 1168: 1165: 1154: 1146: 1140: 1103: 1100: 1099: 1093: 1087: 1071: 1024: 1021: 1020: 977: 974: 973: 947: 921: 918: 917: 901: 898: 897: 862: 859: 858: 841: 837: 835: 832: 831: 811: 807: 792: 788: 783: 780: 779: 763: 760: 759: 710: 707: 706: 684: 681: 680: 658: 655: 654: 620: 617: 616: 588: 585: 584: 568: 565: 564: 530: 527: 526: 406: 403: 402: 397:natural numbers 356: 353: 352: 304: 301: 300: 282: 278: 274: 216: 213: 212: 170: 167: 166: 156: 150: 136:set abstraction 93: 89: 84:The set of all 83: 47: 27: 24: 23: 17: 12: 11: 5: 5948: 5938: 5937: 5932: 5915: 5914: 5912: 5911: 5906: 5904:Thoralf Skolem 5901: 5896: 5891: 5886: 5881: 5876: 5871: 5866: 5861: 5856: 5850: 5848: 5842: 5841: 5839: 5838: 5833: 5828: 5822: 5820: 5818: 5817: 5814: 5808: 5805: 5804: 5802: 5801: 5800: 5799: 5794: 5789: 5788: 5787: 5772: 5771: 5770: 5758: 5757: 5756: 5745: 5744: 5739: 5734: 5729: 5723: 5721: 5717: 5716: 5714: 5713: 5708: 5703: 5698: 5689: 5684: 5679: 5669: 5664: 5663: 5662: 5657: 5652: 5642: 5632: 5627: 5622: 5616: 5614: 5607: 5606: 5604: 5603: 5598: 5593: 5588: 5586:Ordinal number 5583: 5578: 5573: 5568: 5567: 5566: 5561: 5551: 5546: 5541: 5536: 5531: 5521: 5516: 5510: 5508: 5506: 5505: 5502: 5498: 5495: 5494: 5492: 5491: 5486: 5481: 5476: 5471: 5466: 5464:Disjoint union 5461: 5456: 5450: 5444: 5442: 5436: 5435: 5433: 5432: 5431: 5430: 5425: 5414: 5413: 5411:Martin's axiom 5408: 5403: 5398: 5393: 5388: 5383: 5378: 5376:Extensionality 5373: 5368: 5363: 5362: 5361: 5356: 5351: 5341: 5335: 5333: 5327: 5326: 5319: 5317: 5315: 5314: 5308: 5306: 5302: 5301: 5294: 5293: 5286: 5279: 5271: 5263: 5262: 5240: 5214: 5202:mathsisfun.com 5189: 5163: 5150: 5137: 5130: 5109: 5108: 5106: 5103: 5102: 5101: 5094: 5091: 5073: 5072: 5039: 5036: 5012: 5009: 5003: 5002: 4999: 4996: 4993: 4990: 4984: 4983: 4980: 4977: 4974: 4971: 4965: 4964: 4883: 4880: 4841: 4838: 4832: 4831: 4789: 4786: 4771: 4768: 4762: 4761: 4701: 4698: 4677: 4674: 4668: 4667: 4604: 4601: 4574: 4571: 4565: 4564: 4561: 4558: 4555: 4552: 4546: 4545: 4488: 4485: 4461: 4458: 4452: 4451: 4440: 4437: 4434: 4431: 4428: 4425: 4422: 4419: 4416: 4413: 4410: 4407: 4404: 4397: 4390: 4387: 4384: 4381: 4378: 4375: 4365: 4354: 4351: 4348: 4345: 4338: 4331: 4328: 4318: 4314: 4313: 4310: 4307: 4283: 4282: 4258: 4256: 4249: 4209:Main article: 4206: 4203: 4190: 4187: 4184: 4181: 4178: 4175: 4172: 4169: 4166: 4163: 4146: 4145: 4134: 4131: 4128: 4125: 4122: 4119: 4116: 4113: 4110: 4107: 4104: 4101: 4098: 4095: 4092: 4089: 4086: 4083: 4080: 4077: 4074: 4071: 4068: 4065: 4062: 4059: 4056: 4003: 4000: 3987: 3984: 3981: 3978: 3975: 3972: 3952: 3949: 3945: 3941: 3937: 3912: 3909: 3904: 3900: 3884: 3883: 3872: 3869: 3866: 3863: 3859: 3855: 3851: 3847: 3843: 3839: 3836: 3833: 3830: 3827: 3824: 3821: 3816: 3812: 3808: 3804: 3800: 3797: 3794: 3780: 3779: 3768: 3765: 3762: 3758: 3754: 3750: 3746: 3742: 3738: 3735: 3732: 3729: 3726: 3723: 3720: 3715: 3711: 3707: 3703: 3699: 3696: 3693: 3676: 3675: 3663: 3660: 3657: 3654: 3651: 3648: 3645: 3642: 3639: 3636: 3633: 3630: 3627: 3624: 3621: 3618: 3615: 3612: 3609: 3606: 3603: 3600: 3597: 3594: 3591: 3588: 3585: 3571: 3570: 3559: 3556: 3553: 3550: 3547: 3544: 3541: 3538: 3535: 3532: 3529: 3526: 3523: 3520: 3517: 3514: 3511: 3508: 3505: 3502: 3499: 3483: 3480: 3479: 3478: 3467: 3464: 3460: 3456: 3453: 3449: 3445: 3442: 3439: 3436: 3433: 3430: 3427: 3424: 3421: 3418: 3414: 3410: 3407: 3404: 3401: 3398: 3395: 3392: 3389: 3362: 3358: 3354: 3351: 3348: 3345: 3342: 3339: 3336: 3316: 3313: 3310: 3307: 3304: 3301: 3281: 3277: 3273: 3270: 3267: 3264: 3261: 3258: 3255: 3252: 3241: 3240: 3228: 3224: 3220: 3217: 3214: 3211: 3208: 3205: 3202: 3199: 3196: 3193: 3190: 3187: 3177: 3165: 3161: 3157: 3154: 3151: 3148: 3145: 3142: 3139: 3136: 3126: 3114: 3110: 3088: 3067: 3064: 3061: 3058: 3055: 3051: 3047: 3044: 3041: 3038: 3035: 3032: 3028: 3024: 3021: 3011: 2998: 2977: 2973: 2969: 2966: 2963: 2960: 2957: 2954: 2940: 2939: 2927: 2924: 2921: 2918: 2915: 2912: 2909: 2906: 2903: 2900: 2897: 2894: 2891: 2888: 2885: 2882: 2879: 2876: 2873: 2870: 2867: 2864: 2861: 2858: 2855: 2852: 2849: 2846: 2843: 2840: 2837: 2814: 2811: 2808: 2805: 2802: 2799: 2796: 2793: 2790: 2787: 2784: 2781: 2772:, we may have 2761: 2758: 2755: 2752: 2749: 2746: 2743: 2740: 2718: 2715: 2714: 2713: 2704:is the set of 2693: 2690: 2687: 2684: 2681: 2678: 2675: 2672: 2669: 2666: 2663: 2660: 2656: 2652: 2649: 2646: 2643: 2640: 2636: 2632: 2629: 2626: 2623: 2620: 2616: 2612: 2609: 2606: 2596: 2578: 2575: 2572: 2569: 2566: 2563: 2560: 2557: 2553: 2549: 2546: 2543: 2540: 2537: 2534: 2531: 2521: 2492: 2489: 2486: 2483: 2480: 2477: 2474: 2471: 2443: 2416: 2413: 2410: 2407: 2404: 2401: 2398: 2394: 2390: 2387: 2384: 2381: 2378: 2375: 2372: 2369: 2365: 2361: 2358: 2355: 2345: 2332: 2328: 2324: 2302:, for a given 2276: 2273: 2270: 2267: 2264: 2261: 2258: 2255: 2252: 2249: 2245: 2241: 2237: 2233: 2230: 2227: 2224: 2221: 2218: 2215: 2205: 2193: 2190: 2187: 2184: 2181: 2178: 2175: 2172: 2169: 2166: 2163: 2160: 2155: 2152: 2148: 2127: 2124: 2121: 2118: 2115: 2112: 2109: 2106: 2103: 2100: 2097: 2094: 2091: 2088: 2085: 2081: 2077: 2074: 2071: 2068: 2063: 2059: 2038: 2035: 2032: 2029: 2026: 2023: 2020: 2017: 2014: 2011: 2008: 2005: 2002: 1999: 1996: 1993: 1990: 1987: 1984: 1980: 1976: 1973: 1970: 1967: 1962: 1958: 1940: 1924: 1921: 1918: 1913: 1909: 1905: 1901: 1897: 1894: 1891: 1871: 1868: 1865: 1862: 1859: 1856: 1836: 1833: 1830: 1826: 1822: 1818: 1814: 1810: 1806: 1803: 1800: 1790: 1778: 1775: 1772: 1769: 1766: 1735: 1732: 1729: 1726: 1723: 1719: 1715: 1712: 1709: 1693: 1690: 1667: 1664: 1661: 1658: 1655: 1648: 1641: 1638: 1599: 1579: 1576: 1573: 1570: 1565: 1561: 1557: 1554: 1551: 1548: 1543: 1539: 1535: 1532: 1529: 1526: 1523: 1503: 1500: 1497: 1494: 1491: 1488: 1485: 1482: 1479: 1476: 1456: 1453: 1450: 1445: 1441: 1437: 1434: 1431: 1428: 1423: 1419: 1398: 1395: 1392: 1389: 1349: 1338:set membership 1334: 1333: 1322: 1319: 1316: 1313: 1310: 1307: 1304: 1301: 1298: 1295: 1292: 1289: 1286: 1276: 1273: 1270: 1267: 1264: 1256: 1253: 1250: 1247: 1244: 1241: 1227: 1226: 1215: 1212: 1209: 1206: 1203: 1200: 1197: 1194: 1191: 1188: 1185: 1164: 1161: 1128: 1125: 1122: 1119: 1116: 1113: 1110: 1107: 1064: 1063: 1052: 1049: 1046: 1043: 1040: 1037: 1034: 1031: 1028: 1014: 1013: 1002: 999: 996: 993: 990: 987: 984: 981: 946: 943: 938: 937: 925: 905: 878: 875: 872: 869: 866: 844: 840: 819: 814: 810: 806: 803: 800: 795: 791: 787: 767: 744: 741: 738: 735: 732: 729: 726: 723: 720: 717: 714: 694: 691: 688: 668: 665: 662: 642: 639: 636: 633: 630: 627: 624: 604: 601: 598: 595: 592: 572: 552: 549: 546: 543: 540: 537: 534: 519: 518: 506: 503: 500: 497: 494: 491: 488: 485: 482: 479: 476: 473: 470: 467: 464: 461: 458: 455: 452: 449: 446: 443: 440: 437: 434: 431: 428: 425: 422: 419: 416: 413: 410: 400: 395:is the set of 384: 381: 378: 375: 372: 369: 366: 363: 360: 350: 338: 335: 332: 329: 326: 323: 320: 317: 314: 311: 308: 287: 286: 262: 259: 256: 253: 250: 247: 244: 241: 238: 235: 232: 229: 226: 223: 220: 210: 198: 195: 192: 189: 186: 183: 180: 177: 174: 152:Main article: 149: 146: 69: 66: 63: 60: 57: 54: 50: 46: 43: 40: 37: 34: 31: 20: 15: 9: 6: 4: 3: 2: 5947: 5936: 5933: 5931: 5928: 5927: 5925: 5910: 5909:Ernst Zermelo 5907: 5905: 5902: 5900: 5897: 5895: 5894:Willard Quine 5892: 5890: 5887: 5885: 5882: 5880: 5877: 5875: 5872: 5870: 5867: 5865: 5862: 5860: 5857: 5855: 5852: 5851: 5849: 5847: 5846:Set theorists 5843: 5837: 5834: 5832: 5829: 5827: 5824: 5823: 5821: 5815: 5813: 5810: 5809: 5806: 5798: 5795: 5793: 5792:Kripke–Platek 5790: 5786: 5783: 5782: 5781: 5778: 5777: 5776: 5773: 5769: 5766: 5765: 5764: 5763: 5759: 5755: 5752: 5751: 5750: 5747: 5746: 5743: 5740: 5738: 5735: 5733: 5730: 5728: 5725: 5724: 5722: 5718: 5712: 5709: 5707: 5704: 5702: 5699: 5697: 5695: 5690: 5688: 5685: 5683: 5680: 5677: 5673: 5670: 5668: 5665: 5661: 5658: 5656: 5653: 5651: 5648: 5647: 5646: 5643: 5640: 5636: 5633: 5631: 5628: 5626: 5623: 5621: 5618: 5617: 5615: 5612: 5608: 5602: 5599: 5597: 5594: 5592: 5589: 5587: 5584: 5582: 5579: 5577: 5574: 5572: 5569: 5565: 5562: 5560: 5557: 5556: 5555: 5552: 5550: 5547: 5545: 5542: 5540: 5537: 5535: 5532: 5529: 5525: 5522: 5520: 5517: 5515: 5512: 5511: 5509: 5503: 5500: 5499: 5496: 5490: 5487: 5485: 5482: 5480: 5477: 5475: 5472: 5470: 5467: 5465: 5462: 5460: 5457: 5454: 5451: 5449: 5446: 5445: 5443: 5441: 5437: 5429: 5428:specification 5426: 5424: 5421: 5420: 5419: 5416: 5415: 5412: 5409: 5407: 5404: 5402: 5399: 5397: 5394: 5392: 5389: 5387: 5384: 5382: 5379: 5377: 5374: 5372: 5369: 5367: 5364: 5360: 5357: 5355: 5352: 5350: 5347: 5346: 5345: 5342: 5340: 5337: 5336: 5334: 5332: 5328: 5323: 5313: 5310: 5309: 5307: 5303: 5299: 5292: 5287: 5285: 5280: 5278: 5273: 5272: 5269: 5250: 5244: 5229: 5225: 5218: 5203: 5199: 5193: 5178: 5174: 5167: 5160: 5154: 5147: 5141: 5133: 5127: 5123: 5122: 5114: 5110: 5100: 5097: 5096: 5090: 5088: 5084: 5080: 5037: 5010: 5008: 5005: 5004: 4997: 4991: 4989: 4986: 4985: 4978: 4972: 4970: 4967: 4966: 4881: 4839: 4837: 4833: 4787: 4769: 4767: 4763: 4699: 4675: 4673: 4669: 4602: 4572: 4570: 4566: 4559: 4553: 4551: 4547: 4486: 4459: 4457: 4453: 4432: 4426: 4423: 4420: 4417: 4414: 4411: 4408: 4405: 4402: 4385: 4382: 4379: 4366: 4349: 4346: 4343: 4329: 4319: 4316: 4315: 4311: 4308: 4306: 4305: 4302: 4299: 4297: 4292: 4290: 4279: 4276:December 2023 4270: 4266: 4262: 4257: 4248: 4247: 4244: 4242: 4238: 4234: 4230: 4226: 4222: 4218: 4212: 4202: 4182: 4173: 4170: 4167: 4164: 4152: 4132: 4123: 4114: 4111: 4108: 4105: 4099: 4096: 4093: 4084: 4072: 4060: 4047: 4046: 4045: 4040:that satisfy 4038: 4032: 4025: 4020:is a set and 4018: 4013: 4009: 3999: 3982: 3979: 3976: 3973: 3950: 3947: 3939: 3926: 3910: 3907: 3902: 3898: 3889: 3870: 3864: 3861: 3853: 3845: 3837: 3834: 3822: 3819: 3814: 3810: 3806: 3798: 3795: 3785: 3784: 3783: 3763: 3760: 3752: 3744: 3736: 3733: 3727: 3721: 3718: 3713: 3709: 3705: 3697: 3694: 3684: 3683: 3682: 3681:For example, 3679: 3652: 3646: 3643: 3640: 3637: 3634: 3619: 3613: 3610: 3607: 3604: 3601: 3589: 3576: 3575: 3574: 3551: 3545: 3542: 3539: 3536: 3533: 3527: 3518: 3512: 3509: 3506: 3503: 3500: 3490: 3489: 3488: 3465: 3454: 3451: 3447: 3440: 3437: 3434: 3428: 3425: 3419: 3408: 3405: 3402: 3399: 3396: 3393: 3390: 3380: 3379: 3378: 3376: 3360: 3356: 3349: 3346: 3343: 3337: 3334: 3314: 3311: 3308: 3305: 3302: 3299: 3271: 3268: 3265: 3262: 3259: 3256: 3253: 3218: 3215: 3212: 3206: 3203: 3200: 3197: 3194: 3191: 3178: 3155: 3152: 3149: 3146: 3143: 3140: 3137: 3127: 3112: 3062: 3059: 3056: 3053: 3045: 3042: 3039: 3036: 3033: 3030: 3026: 3022: 3012: 2967: 2964: 2961: 2958: 2955: 2945: 2944: 2943: 2942:For example: 2916: 2907: 2901: 2895: 2892: 2889: 2883: 2877: 2874: 2868: 2859: 2850: 2844: 2838: 2828: 2827: 2826: 2812: 2803: 2794: 2788: 2782: 2753: 2744: 2741: 2730: 2725: 2711: 2707: 2685: 2682: 2679: 2676: 2673: 2670: 2667: 2664: 2650: 2647: 2630: 2627: 2618: 2610: 2607: 2597: 2593: 2570: 2567: 2564: 2561: 2547: 2544: 2535: 2532: 2522: 2517: 2513: 2507: 2487: 2481: 2475: 2461: 2457: 2441: 2433: 2430: 2408: 2405: 2402: 2399: 2396: 2388: 2385: 2376: 2367: 2359: 2356: 2346: 2326: 2314: 2311:. Here the 2309: 2305: 2299: 2295: 2290: 2268: 2262: 2259: 2256: 2253: 2250: 2247: 2239: 2231: 2225: 2222: 2219: 2206: 2188: 2185: 2182: 2179: 2176: 2173: 2170: 2167: 2164: 2158: 2153: 2150: 2146: 2122: 2119: 2116: 2113: 2110: 2107: 2104: 2098: 2092: 2089: 2086: 2083: 2075: 2072: 2066: 2061: 2057: 2033: 2030: 2027: 2024: 2021: 2018: 2015: 2012: 2009: 2006: 2003: 1997: 1991: 1988: 1985: 1982: 1974: 1971: 1965: 1960: 1956: 1946: 1941: 1938: 1919: 1916: 1911: 1907: 1903: 1895: 1892: 1866: 1863: 1860: 1857: 1831: 1828: 1820: 1812: 1804: 1801: 1791: 1770: 1767: 1756: 1752: 1749: 1730: 1727: 1724: 1721: 1713: 1710: 1700: 1699: 1698: 1689: 1685: 1679: 1665: 1659: 1656: 1653: 1639: 1628: 1624: 1620: 1616: 1611: 1597: 1571: 1563: 1555: 1549: 1541: 1533: 1530: 1527: 1524: 1495: 1486: 1483: 1480: 1477: 1451: 1443: 1435: 1429: 1421: 1393: 1380:" below). If 1379: 1374: 1368: 1363: 1347: 1339: 1320: 1311: 1302: 1299: 1296: 1293: 1290: 1287: 1268: 1254: 1251: 1248: 1245: 1242: 1232: 1231: 1230: 1213: 1204: 1195: 1192: 1189: 1186: 1176: 1175: 1174: 1171: 1160: 1157: 1152: 1143: 1120: 1111: 1108: 1096: 1090: 1085: 1081: 1075: 1069: 1050: 1041: 1032: 1029: 1019: 1018: 1017: 994: 985: 982: 972: 971: 970: 968: 964: 960: 956: 952: 942: 896: 895: 894: 890: 876: 873: 870: 867: 864: 842: 838: 812: 808: 804: 801: 798: 793: 789: 778:. Similarly, 758: 739: 736: 733: 730: 727: 721: 715: 692: 689: 686: 663: 637: 634: 631: 628: 625: 602: 599: 596: 593: 590: 570: 547: 544: 541: 538: 535: 523: 501: 498: 495: 492: 489: 486: 483: 480: 477: 474: 471: 468: 465: 459: 453: 450: 447: 444: 441: 438: 435: 432: 429: 426: 423: 420: 417: 414: 411: 401: 398: 379: 376: 373: 370: 367: 364: 361: 351: 333: 330: 327: 324: 321: 318: 315: 312: 309: 299: 298: 297: 295: 290: 257: 254: 251: 248: 245: 239: 233: 230: 227: 224: 221: 211: 193: 190: 187: 184: 181: 178: 175: 165: 164: 163: 161: 155: 145: 143: 142: 137: 133: 128: 126: 122: 118: 114: 110: 106: 102: 98: 92: 87: 86:even integers 80: 64: 61: 58: 55: 52: 44: 41: 35: 32: 19: 5859:Georg Cantor 5854:Paul Bernays 5785:Morse–Kelley 5760: 5693: 5692:Subset  5639:hereditarily 5601:Venn diagram 5590: 5559:ordered pair 5474:Intersection 5418:Axiom schema 5253:. Retrieved 5243: 5231:. Retrieved 5227: 5217: 5205:. Retrieved 5201: 5192: 5180:. Retrieved 5176: 5166: 5158: 5153: 5145: 5140: 5120: 5113: 5087:zero element 5078: 5076: 4317:Set-builder 4300: 4293: 4286: 4273: 4214: 4150: 4147: 4036: 4030: 4023: 4016: 4005: 3924: 3887: 3885: 3781: 3680: 3677: 3572: 3485: 3374: 3242: 2941: 2723: 2720: 2591: 2515: 2511: 2505: 2307: 2297: 2293: 2288: 1944: 1751:real numbers 1695: 1683: 1680: 1622: 1612: 1372: 1366: 1340:, while the 1335: 1228: 1169: 1166: 1155: 1141: 1094: 1088: 1083: 1079: 1073: 1067: 1065: 1015: 967:vertical bar 958: 954: 948: 939: 891: 525:In general, 524: 520: 291: 288: 157: 139: 135: 131: 129: 112: 94: 82: 22: 18: 5884:Thomas Jech 5727:Alternative 5706:Uncountable 5660:Ultrafilter 5519:Cardinality 5423:replacement 5371:Determinacy 5007:Mathematica 1847:is the set 705:, in which 105:mathematics 5930:Set theory 5924:Categories 5879:Kurt Gödel 5864:Paul Cohen 5701:Transitive 5469:Identities 5453:Complement 5440:Operations 5401:Regularity 5339:Adjunction 5298:Set theory 4312:Example 2 3890:, we have 2729:expression 2509:such that 583:such that 97:set theory 5812:Paradoxes 5732:Axiomatic 5711:Universal 5687:Singleton 5682:Recursive 5625:Countable 5620:Amorphous 5479:Power set 5396:Power set 5354:dependent 5349:countable 5207:20 August 5182:20 August 4424:∧ 4418:∈ 4412:∧ 4406:∈ 4347:∈ 4309:Example 1 4289:generator 4227:) is the 4219:(notably 4177:Φ 4174:∣ 4168:∈ 4118:Φ 4115:∧ 4109:∈ 4103:⇔ 4097:∈ 4082:∀ 4070:∃ 4058:∀ 3974:− 3846:∧ 3838:∈ 3829:⇔ 3807:∧ 3799:∈ 3745:∣ 3737:∈ 3706:∣ 3698:∈ 3644:∧ 3638:∈ 3629:⇔ 3611:∧ 3605:∈ 3587:∀ 3543:∣ 3537:∈ 3510:∣ 3504:∈ 3455:∈ 3438:− 3429:∣ 3409:∈ 3403:∣ 3347:− 3272:∈ 3266:∣ 3219:∈ 3213:∣ 3156:∈ 3150:∣ 3046:∈ 3034:∣ 2968:∈ 2962:∣ 2911:Φ 2908:∧ 2881:∃ 2878:∣ 2854:Φ 2851:∣ 2798:Φ 2795:∣ 2748:Φ 2745:∣ 2674:∧ 2651:∈ 2645:∃ 2631:∈ 2625:∃ 2619:∣ 2611:∈ 2548:∈ 2542:∃ 2536:∣ 2473:∃ 2442:∧ 2397:∧ 2389:∈ 2374:∃ 2368:∣ 2360:∈ 2327:× 2248:∣ 2240:× 2232:∈ 2189:… 2174:− 2165:− 2151:− 2123:… 2090:≥ 2084:∣ 2076:∈ 2034:… 1989:≥ 1983:∣ 1975:∈ 1904:∣ 1896:∈ 1858:− 1813:∣ 1805:∈ 1774:∞ 1722:∣ 1714:∈ 1598:∧ 1560:Φ 1538:Φ 1534:∣ 1528:∈ 1490:Φ 1487:∣ 1481:∈ 1440:Φ 1436:∧ 1418:Φ 1388:Φ 1348:∧ 1306:Φ 1303:∧ 1297:∈ 1291:∣ 1263:Φ 1252:∈ 1246:∣ 1199:Φ 1196:∣ 1190:∈ 1167:A domain 1151:empty set 1115:Φ 1112:∣ 1084:predicate 1068:such that 1036:Φ 989:Φ 986:∣ 951:predicate 874:≤ 868:≤ 802:… 766:∅ 757:empty set 734:… 632:… 600:≤ 594:≤ 542:… 502:… 493:− 478:− 454:… 427:− 418:− 412:… 380:… 328:… 141:intension 45:∈ 39:∃ 36:∣ 5816:Problems 5720:Theories 5696:Superset 5672:Infinite 5501:Concepts 5381:Infinity 5305:Overview 5255:6 August 5233:6 August 5093:See also 4148:The set 3078:, where 3060:≠ 2988:, where 2727:with an 2710:integers 2668:≠ 2304:function 1748:positive 1692:Examples 1657:∉ 294:ellipsis 125:elements 5754:General 5749:Zermelo 5655:subbase 5637: ( 5576:Forcing 5554:Element 5526: ( 5504:Methods 5391:Pairing 5251:. Scala 5085:with a 4550:Haskell 4269:Discuss 4225:Haskell 1467:, then 1082:or the 1072:Φ( 5645:Filter 5635:Finite 5571:Family 5514:Almost 5359:global 5344:Choice 5331:Axioms 5128:  5020:|-> 4969:Erlang 4957:Result 4921:member 4903:member 4873:Result 4855:member 4836:Prolog 4791:SELECT 4773:SELECT 4742:select 4691:select 4456:Python 4400:  4392:  4341:  4333:  4237:filter 4221:Python 2434:. The 1939:below. 1935:; see 1651:  1643:  1619:subset 1147:Φ 281:, and 107:, and 5737:Naive 5667:Fuzzy 5630:Empty 5613:types 5564:tuple 5534:Class 5528:large 5489:Union 5406:Union 5173:"Set" 5105:Notes 5083:monad 5041:Cases 4988:Julia 4885:setof 4843:setof 4815:WHERE 4812:X_set 4806:K_set 4782:L_set 4727:where 4648:yield 4627:<- 4615:<- 4594:yield 4585:<- 4569:Scala 4296:Scala 4263:into 4261:moved 4241:lists 963:colon 959:false 115:is a 101:logic 5650:base 5257:2017 5235:2017 5209:2020 5184:2020 5126:ISBN 4939:call 4803:FROM 4779:FROM 4715:from 4703:from 4679:from 4235:and 4223:and 2429:even 2260:< 2254:< 2138:and 1728:> 1080:rule 955:true 857:for 5611:Set 4954:)), 4900:),( 4766:SQL 4606:for 4576:for 4517:for 4505:for 4469:for 4271:) 4267:. ( 4233:map 1757:as 1621:of 1016:or 965:or 334:100 160:set 121:set 95:In 5926:: 5226:. 5200:. 5175:. 5089:. 5062:/; 5056:x_ 5050:k_ 5029:/@ 4936:), 4933:Xs 4918:), 4915:Ks 4888:(( 4870:), 4867:Ls 4721:in 4709:in 4685:in 4672:C# 4645:)) 4633:if 4541:)} 4529:if 4523:in 4511:in 4490:{( 4475:in 4243:. 4201:. 4044:: 4022:Φ( 3998:. 2520:". 1610:. 1280:or 889:. 277:, 194:31 188:15 158:A 144:. 134:, 111:, 103:, 88:, 5694:· 5678:) 5674:( 5641:) 5530:) 5290:e 5283:t 5276:v 5259:. 5237:. 5211:. 5186:. 5134:. 5068:] 5065:P 5059:} 5053:, 5047:{ 5044:, 5032:L 5026:) 5023:l 5017:l 5014:( 4960:) 4951:X 4948:, 4945:P 4942:( 4930:, 4927:X 4924:( 4912:, 4909:K 4906:( 4897:X 4894:, 4891:K 4876:) 4864:, 4861:L 4858:( 4852:, 4849:L 4846:( 4827:) 4824:x 4821:( 4818:P 4809:, 4800:x 4797:, 4794:k 4776:l 4757:) 4754:x 4751:, 4748:k 4745:( 4739:) 4736:x 4733:( 4730:P 4724:X 4718:x 4712:K 4706:k 4694:l 4688:L 4682:l 4663:) 4660:x 4657:, 4654:k 4651:( 4642:x 4639:( 4636:P 4630:X 4624:x 4621:; 4618:K 4612:k 4609:( 4597:l 4591:) 4588:L 4582:l 4579:( 4538:x 4535:( 4532:P 4526:X 4520:x 4514:K 4508:k 4502:) 4499:x 4496:, 4493:k 4481:} 4478:L 4472:l 4466:l 4463:{ 4439:} 4436:) 4433:x 4430:( 4427:P 4421:X 4415:x 4409:K 4403:k 4396:| 4389:) 4386:x 4383:, 4380:k 4377:( 4374:{ 4353:} 4350:L 4344:l 4337:| 4330:l 4327:{ 4278:) 4274:( 4189:} 4186:) 4183:x 4180:( 4171:E 4165:x 4162:{ 4151:Y 4133:. 4130:] 4127:) 4124:x 4121:( 4112:E 4106:x 4100:Y 4094:x 4091:[ 4088:) 4085:x 4079:( 4076:) 4073:Y 4067:( 4064:) 4061:E 4055:( 4042:Φ 4037:E 4031:Y 4026:) 4024:x 4017:E 3986:} 3983:1 3980:, 3977:1 3971:{ 3951:1 3948:= 3944:| 3940:x 3936:| 3925:x 3911:1 3908:= 3903:2 3899:x 3888:x 3871:. 3868:) 3865:1 3862:= 3858:| 3854:x 3850:| 3842:Q 3835:x 3832:( 3826:) 3823:1 3820:= 3815:2 3811:x 3803:R 3796:x 3793:( 3767:} 3764:1 3761:= 3757:| 3753:x 3749:| 3741:Q 3734:x 3731:{ 3728:= 3725:} 3722:1 3719:= 3714:2 3710:x 3702:R 3695:x 3692:{ 3674:. 3662:] 3659:) 3656:) 3653:t 3650:( 3647:Q 3641:B 3635:t 3632:( 3626:) 3623:) 3620:t 3617:( 3614:P 3608:A 3602:t 3599:( 3596:[ 3593:) 3590:t 3584:( 3558:} 3555:) 3552:x 3549:( 3546:Q 3540:B 3534:x 3531:{ 3528:= 3525:} 3522:) 3519:x 3516:( 3513:P 3507:A 3501:x 3498:{ 3466:. 3463:} 3459:Z 3452:2 3448:/ 3444:) 3441:1 3435:u 3432:( 3426:u 3423:{ 3420:= 3417:} 3413:Z 3406:t 3400:1 3397:+ 3394:t 3391:2 3388:{ 3375:t 3361:2 3357:/ 3353:) 3350:1 3344:u 3341:( 3338:= 3335:t 3315:1 3312:+ 3309:t 3306:2 3303:= 3300:u 3280:} 3276:Z 3269:t 3263:1 3260:+ 3257:t 3254:2 3251:{ 3227:} 3223:Z 3216:t 3210:) 3207:1 3204:+ 3201:t 3198:2 3195:, 3192:t 3189:( 3186:{ 3164:} 3160:Z 3153:t 3147:1 3144:+ 3141:t 3138:2 3135:{ 3113:, 3109:Q 3087:Z 3066:} 3063:0 3057:q 3054:, 3050:Z 3043:q 3040:, 3037:p 3031:q 3027:/ 3023:p 3020:{ 2997:N 2976:} 2972:N 2965:n 2959:n 2956:2 2953:{ 2938:. 2926:} 2923:) 2920:) 2917:x 2914:( 2905:) 2902:x 2899:( 2896:f 2893:= 2890:y 2887:( 2884:x 2875:y 2872:{ 2869:= 2866:} 2863:) 2860:x 2857:( 2848:) 2845:x 2842:( 2839:f 2836:{ 2813:, 2810:} 2807:) 2804:x 2801:( 2792:) 2789:x 2786:( 2783:f 2780:{ 2760:} 2757:) 2754:x 2751:( 2742:x 2739:{ 2724:x 2712:. 2692:} 2689:] 2686:p 2683:= 2680:q 2677:a 2671:0 2665:q 2662:[ 2659:) 2655:Z 2648:q 2642:( 2639:) 2635:Z 2628:p 2622:( 2615:R 2608:a 2605:{ 2592:n 2577:} 2574:] 2571:k 2568:2 2565:= 2562:n 2559:[ 2556:) 2552:N 2545:k 2539:( 2533:n 2530:{ 2518:) 2516:x 2514:( 2512:P 2506:x 2491:) 2488:x 2485:( 2482:P 2479:) 2476:x 2470:( 2415:} 2412:] 2409:k 2406:2 2403:= 2400:n 2393:N 2386:k 2383:[ 2380:) 2377:k 2371:( 2364:N 2357:n 2354:{ 2331:R 2323:R 2308:f 2300:) 2298:x 2296:( 2294:f 2289:y 2275:} 2272:) 2269:x 2266:( 2263:f 2257:y 2251:0 2244:R 2236:R 2229:) 2226:y 2223:, 2220:x 2217:( 2214:{ 2204:. 2192:} 2186:, 2183:0 2180:, 2177:1 2171:, 2168:2 2162:{ 2159:= 2154:2 2147:G 2126:} 2120:, 2117:5 2114:, 2111:4 2108:, 2105:3 2102:{ 2099:= 2096:} 2093:3 2087:x 2080:Z 2073:x 2070:{ 2067:= 2062:3 2058:G 2037:} 2031:, 2028:2 2025:+ 2022:m 2019:, 2016:1 2013:+ 2010:m 2007:, 2004:m 2001:{ 1998:= 1995:} 1992:m 1986:x 1979:Z 1972:x 1969:{ 1966:= 1961:m 1957:G 1945:m 1923:} 1920:1 1917:= 1912:2 1908:x 1900:R 1893:x 1890:{ 1870:} 1867:1 1864:, 1861:1 1855:{ 1835:} 1832:1 1829:= 1825:| 1821:x 1817:| 1809:R 1802:x 1799:{ 1789:. 1777:) 1771:, 1768:0 1765:( 1734:} 1731:0 1725:x 1718:R 1711:x 1708:{ 1684:E 1666:, 1663:} 1660:x 1654:x 1647:| 1640:x 1637:{ 1578:} 1575:) 1572:x 1569:( 1564:2 1556:, 1553:) 1550:x 1547:( 1542:1 1531:E 1525:x 1522:{ 1502:} 1499:) 1496:x 1493:( 1484:E 1478:x 1475:{ 1455:) 1452:x 1449:( 1444:2 1433:) 1430:x 1427:( 1422:1 1397:) 1394:x 1391:( 1373:E 1367:x 1321:. 1318:} 1315:) 1312:x 1309:( 1300:E 1294:x 1288:x 1285:{ 1275:} 1272:) 1269:x 1266:( 1255:E 1249:x 1243:x 1240:{ 1214:, 1211:} 1208:) 1205:x 1202:( 1193:E 1187:x 1184:{ 1170:E 1156:x 1142:x 1127:} 1124:) 1121:x 1118:( 1109:x 1106:{ 1095:x 1089:x 1076:) 1074:x 1051:. 1048:} 1045:) 1042:x 1039:( 1033:: 1030:x 1027:{ 1001:} 998:) 995:x 992:( 983:x 980:{ 924:} 904:{ 877:n 871:i 865:1 843:i 839:a 818:} 813:n 809:a 805:, 799:, 794:1 790:a 786:{ 743:} 740:0 737:, 731:, 728:1 725:{ 722:= 719:] 716:0 713:[ 693:0 690:= 687:n 667:] 664:n 661:[ 641:} 638:n 635:, 629:, 626:1 623:{ 603:n 597:i 591:1 571:i 551:} 548:n 545:, 539:, 536:1 533:{ 505:} 499:, 496:2 490:, 487:2 484:, 481:1 475:, 472:1 469:, 466:0 463:{ 460:= 457:} 451:, 448:2 445:, 442:1 439:, 436:0 433:, 430:1 424:, 421:2 415:, 409:{ 399:. 383:} 377:, 374:3 371:, 368:2 365:, 362:1 359:{ 337:} 331:, 325:, 322:3 319:, 316:2 313:, 310:1 307:{ 283:c 279:b 275:a 261:} 258:c 255:, 252:b 249:, 246:a 243:{ 240:= 237:} 234:b 231:, 228:c 225:, 222:a 219:{ 197:} 191:, 185:, 182:3 179:, 176:7 173:{ 68:} 65:k 62:2 59:= 56:n 53:, 49:Z 42:k 33:n 30:{

Index

even integers
set theory
logic
mathematics
computer science
mathematical notation
set
elements
intension
Set (mathematics) § Roster notation
set
ellipsis
natural numbers
empty set
predicate
colon
vertical bar
empty set
set membership
logical conjunction
Set existence axiom
domain of discourse
subset
Russell's paradox
positive
real numbers
interval notation
equivalent predicates yield equal sets
function
cartesian product

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