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Large set (Ramsey theory)

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is large if and only if every finite partition of the natural numbers has a cell containing arbitrarily long arithmetic progressions having common differences in
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It is unknown whether there are 2-large sets that are not also large sets. Brown, Graham, and Landman (1999) conjecture that no such sets exists.
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Sets big enough to assert the existence of arithmetic progressions with common difference
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must contain at least one multiple (equivalently, infinitely many multiples) of
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The natural numbers are large. This is precisely the assertion of
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Every set is either large or 624: 598: 578: 558: 528: 470: 469: 461: 400: 365: 345: 326: 325: 315: 314: 300: 229: 216: 203: 188: 84:Learn how and when to remove this message 395:and positive leading coefficient, then 434:Other facts about large sets include: 7: 775:Mathworld: van der Waerden's Theorem 632: 254:is large, it is not the case that 14: 168:is large, for any natural number 800:Theorems in discrete mathematics 30: 625: 276:Two sufficient conditions are: 746:Canadian Mathematical Bulletin 636: 626: 376: 370: 319: 311: 1: 790:Basic concepts in set theory 151:The even numbers are large. 816: 123:with common difference in 21:Large set (disambiguation) 18: 739:; Landman, Bruce (1999). 674:van der Waerden's theorem 146:Van der Waerden's theorem 117:Van der Waerden's theorem 699:-1)-largeness for k>1 684:-large for some maximal 657:2-large and k-large sets 542:{\displaystyle k\cdot S} 39:This article includes a 676:is concerned only with 668:, for a natural number 573:is large, then for any 121:arithmetic progressions 68:more precise citations. 760:10.4153/cmb-1999-003-9 647: 587: 567: 543: 514: 409: 389: 388:{\displaystyle p(0)=0} 354: 334: 248: 111:is considered to be a 648: 588: 568: 544: 515: 410: 390: 360:is a polynomial with 355: 335: 284:contains n-cubes for 249: 695:-largeness implies ( 597: 577: 557: 527: 460: 399: 364: 344: 299: 187: 19:For other uses, see 705:-largeness for all 723:Partition of a set 709:implies largeness. 643: 583: 563: 539: 510: 405: 385: 350: 330: 244: 41:list of references 586:{\displaystyle m} 566:{\displaystyle S} 408:{\displaystyle S} 353:{\displaystyle p} 286:arbitrarily large 94: 93: 86: 807: 764: 762: 652: 650: 649: 644: 639: 592: 590: 589: 584: 572: 570: 569: 564: 548: 546: 545: 540: 519: 517: 516: 511: 473: 446:is finite, then 414: 412: 411: 406: 394: 392: 391: 386: 359: 357: 356: 351: 339: 337: 336: 331: 329: 318: 253: 251: 250: 245: 234: 233: 221: 220: 208: 207: 89: 82: 78: 75: 69: 64:this article by 55:inline citations 34: 33: 26: 815: 814: 810: 809: 808: 806: 805: 804: 780: 779: 771: 734: 731: 729:Further reading 719: 659: 595: 594: 575: 574: 555: 554: 525: 524: 523:If S is large, 458: 457: 397: 396: 362: 361: 342: 341: 297: 296: 267: 260: 225: 212: 199: 185: 184: 158: 141: 115:if and only if 109:natural numbers 90: 79: 73: 70: 59: 45:related reading 35: 31: 24: 17: 12: 11: 5: 813: 811: 803: 802: 797: 792: 782: 781: 778: 777: 770: 769:External links 767: 766: 765: 737:Graham, Ronald 730: 727: 726: 725: 718: 715: 711: 710: 700: 658: 655: 642: 638: 635: 631: 628: 623: 620: 617: 614: 611: 608: 605: 602: 582: 562: 551: 550: 549:is also large. 538: 535: 532: 521: 509: 506: 503: 500: 497: 494: 491: 488: 485: 482: 479: 476: 472: 468: 465: 455: 417: 416: 404: 384: 381: 378: 375: 372: 369: 349: 328: 324: 321: 317: 313: 310: 307: 304: 293: 274: 273: 265: 258: 243: 240: 237: 232: 228: 224: 219: 215: 211: 206: 202: 198: 195: 192: 181: 157: 154: 153: 152: 149: 140: 137: 92: 91: 74:September 2015 49:external links 38: 36: 29: 15: 13: 10: 9: 6: 4: 3: 2: 812: 801: 798: 796: 795:Ramsey theory 793: 791: 788: 787: 785: 776: 773: 772: 768: 761: 756: 752: 748: 747: 742: 738: 733: 732: 728: 724: 721: 720: 716: 714: 708: 704: 701: 698: 694: 691: 690: 689: 687: 683: 679: 675: 671: 667: 665: 656: 654: 633: 629: 621: 618: 615: 612: 609: 603: 600: 580: 560: 536: 533: 530: 522: 504: 501: 498: 495: 492: 489: 486: 483: 480: 474: 466: 463: 456: 453: 451: 445: 442:is large and 441: 437: 436: 435: 432: 430: 426: 422: 402: 382: 379: 373: 367: 347: 322: 308: 305: 302: 294: 291: 287: 283: 279: 278: 277: 271: 264: 257: 238: 235: 230: 226: 222: 217: 213: 209: 204: 200: 193: 190: 182: 179: 175: 171: 167: 163: 162: 161: 155: 150: 147: 143: 142: 138: 136: 134: 130: 126: 122: 118: 114: 110: 106: 103: 99: 98:Ramsey theory 88: 85: 77: 67: 63: 57: 56: 50: 46: 42: 37: 28: 27: 22: 753:(1): 25–36. 750: 744: 735:Brown, Tom; 712: 706: 702: 696: 692: 685: 681: 677: 669: 663: 662: 660: 552: 447: 443: 439: 433: 428: 420: 418: 289: 281: 275: 269: 262: 255: 177: 173: 169: 165: 159: 132: 128: 127:. That is, 124: 112: 104: 95: 80: 71: 60:Please help 52: 66:introducing 784:Categories 653:is large. 431:is large. 156:Properties 661:A set is 619:≡ 604:∩ 534:⋅ 520:is large. 505:… 467:⋅ 454:is large. 425:thick set 415:is large. 323:∩ 292:is large. 239:… 113:large set 717:See also 288:n, then 139:Examples 452: F 448:S  427:, then 62:improve 666:-large 340:where 423:is a 47:, or 272:≥ 2. 268:for 100:, a 755:doi 630:mod 553:If 438:If 295:If 280:If 266:k-1 183:If 164:If 107:of 102:set 96:In 786:: 751:42 749:. 743:. 593:, 261:≥3 172:, 135:. 51:, 43:, 763:. 757:: 707:k 703:k 697:k 693:k 686:k 682:k 678:k 670:k 664:k 641:} 637:) 634:m 627:( 622:0 616:x 613:: 610:x 607:{ 601:S 581:m 561:S 537:S 531:k 508:} 502:, 499:k 496:3 493:, 490:k 487:2 484:, 481:k 478:{ 475:= 471:N 464:k 450:– 444:F 440:S 429:S 421:S 403:S 383:0 380:= 377:) 374:0 371:( 368:p 348:p 327:N 320:) 316:N 312:( 309:p 306:= 303:S 290:S 282:S 270:k 263:s 259:k 256:s 242:} 236:, 231:3 227:s 223:, 218:2 214:s 210:, 205:1 201:s 197:{ 194:= 191:S 180:. 178:n 174:S 170:n 166:S 148:. 133:S 129:S 125:S 105:S 87:) 81:( 76:) 72:( 58:. 23:.

Index

Large set (disambiguation)
list of references
related reading
external links
inline citations
improve
introducing
Learn how and when to remove this message
Ramsey theory
set
natural numbers
Van der Waerden's theorem
arithmetic progressions
Van der Waerden's theorem
arbitrarily large
thick set

van der Waerden's theorem
Partition of a set
Graham, Ronald
"On the Set of Common Differences in van der Waerden's Theorem on Arithmetic Progressions"
Canadian Mathematical Bulletin
doi
10.4153/cmb-1999-003-9
Mathworld: van der Waerden's Theorem
Categories
Basic concepts in set theory
Ramsey theory
Theorems in discrete mathematics

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