Knowledge

Computable ordinal

Source đź“ť

384: 260: 219: 178: 293: 118: 95: 49: 425: 368: 352: 344: 228: 187: 146: 449: 418: 459: 274: 454: 411: 310: 305: 140: 129: 103: 80: 34: 399: 21: 8: 444: 333: 364: 348: 340: 125: 121: 320: 315: 266: 71: 221:. Since there are only countably many computable relations, there are also only 395: 60: 29: 438: 270: 222: 181: 357: 17: 391: 75: 63: 25: 136: 67: 363:. Perspectives in mathematical logic, Springer-Verlag, 1990. 265:
The computable ordinals are exactly the ordinals that have an
383: 337:
The Theory of Recursive Functions and Effective Computability
184:. An ordinal is computable if and only if it is smaller than 277: 231: 190: 149: 106: 83: 37: 287: 254: 213: 172: 112: 89: 43: 143:, the first nonrecursive ordinal, and denoted by 436: 124:of a computable ordinal is computable, and the 419: 426: 412: 255:{\displaystyle \omega _{1}^{\mathsf {CK}}} 214:{\displaystyle \omega _{1}^{\mathsf {CK}}} 173:{\displaystyle \omega _{1}^{\mathsf {CK}}} 139:of all computable ordinals is called the 437: 246: 243: 205: 202: 164: 161: 378: 339:, 1967. Reprinted 1987, MIT Press, 13: 280: 14: 471: 180:. The Church–Kleene ordinal is a 382: 225:many computable ordinals. Thus, 288:{\displaystyle {\mathcal {O}}} 128:of all computable ordinals is 1: 326: 398:. You can help Knowledge by 7: 299: 10: 476: 377: 100:It is easy to check that 361:Higher Recursion Theory 311:Large countable ordinal 113:{\displaystyle \omega } 90:{\displaystyle \alpha } 44:{\displaystyle \alpha } 394:-related article is a 306:Arithmetical hierarchy 289: 256: 215: 174: 114: 91: 45: 290: 257: 216: 175: 141:Church–Kleene ordinal 115: 92: 46: 450:Computability theory 275: 229: 188: 147: 104: 81: 35: 251: 210: 169: 120:is computable. The 334:Hartley Rogers Jr. 285: 252: 232: 211: 191: 170: 150: 110: 87: 41: 407: 406: 467: 460:Set theory stubs 428: 421: 414: 386: 379: 321:Ordinal notation 316:Ordinal analysis 294: 292: 291: 286: 284: 283: 267:ordinal notation 261: 259: 258: 253: 250: 249: 240: 220: 218: 217: 212: 209: 208: 199: 179: 177: 176: 171: 168: 167: 158: 119: 117: 116: 111: 96: 94: 93: 88: 66:of a computable 50: 48: 47: 42: 475: 474: 470: 469: 468: 466: 465: 464: 455:Ordinal numbers 435: 434: 433: 432: 375: 373: 329: 302: 279: 278: 276: 273: 272: 242: 241: 236: 230: 227: 226: 201: 200: 195: 189: 186: 185: 160: 159: 154: 148: 145: 144: 105: 102: 101: 82: 79: 78: 72:natural numbers 36: 33: 32: 20:, specifically 12: 11: 5: 473: 463: 462: 457: 452: 447: 431: 430: 423: 416: 408: 405: 404: 387: 372: 371: 355: 330: 328: 325: 324: 323: 318: 313: 308: 301: 298: 282: 262:is countable. 248: 245: 239: 235: 207: 204: 198: 194: 166: 163: 157: 153: 109: 86: 59:if there is a 51:is said to be 40: 9: 6: 4: 3: 2: 472: 461: 458: 456: 453: 451: 448: 446: 443: 442: 440: 429: 424: 422: 417: 415: 410: 409: 403: 401: 397: 393: 388: 385: 381: 380: 376: 370: 369:0-387-19305-7 366: 362: 359: 356: 354: 353:0-07-053522-1 350: 347:(paperback), 346: 345:0-262-68052-1 342: 338: 335: 332: 331: 322: 319: 317: 314: 312: 309: 307: 304: 303: 297: 295: 268: 263: 237: 233: 224: 196: 192: 183: 182:limit ordinal 155: 151: 142: 138: 133: 132:downwards. 131: 127: 123: 107: 98: 84: 77: 73: 69: 65: 64:well-ordering 62: 58: 54: 38: 31: 27: 23: 22:computability 19: 400:expanding it 389: 374: 360: 358:Gerald Sacks 336: 264: 134: 99: 56: 52: 15: 74:having the 18:mathematics 445:Set theory 439:Categories 392:set theory 327:References 76:order type 61:computable 53:computable 26:set theory 271:Kleene's 234:ω 223:countably 193:ω 152:ω 122:successor 108:ω 85:α 57:recursive 39:α 300:See also 137:supremum 70:of the 30:ordinal 367:  351:  343:  130:closed 68:subset 390:This 28:, an 396:stub 365:ISBN 349:ISBN 341:ISBN 135:The 24:and 296:. 269:in 126:set 55:or 16:In 441:: 97:. 427:e 420:t 413:v 402:. 281:O 247:K 244:C 238:1 206:K 203:C 197:1 165:K 162:C 156:1

Index

mathematics
computability
set theory
ordinal
computable
well-ordering
subset
natural numbers
order type
successor
set
closed
supremum
Church–Kleene ordinal
limit ordinal
countably
ordinal notation
Kleene's O {\displaystyle {\mathcal {O}}}
Arithmetical hierarchy
Large countable ordinal
Ordinal analysis
Ordinal notation
Hartley Rogers Jr.
ISBN
0-262-68052-1
ISBN
0-07-053522-1
Gerald Sacks
ISBN
0-387-19305-7

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

↑