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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 635: 609: 589: 569: 539: 481: 480: 472: 411: 376: 356: 337: 336: 326: 325: 311: 240: 227: 214: 199: 95:Learn how and when to remove this message 406:and positive leading coefficient, then 445:Other facts about large sets include: 7: 786:Mathworld: van der Waerden's Theorem 643: 265:is large, it is not the case that 25: 179:is large, for any natural number 811:Theorems in discrete mathematics 41: 636: 287:Two sufficient conditions are: 757:Canadian Mathematical Bulletin 647: 637: 387: 381: 330: 322: 1: 801:Basic concepts in set theory 162:The even numbers are large. 827: 134:with common difference in 32:Large set (disambiguation) 29: 750:; Landman, Bruce (1999). 685:van der Waerden's theorem 157:Van der Waerden's theorem 128:Van der Waerden's theorem 18:Small set (Ramsey theory) 710:-1)-largeness for k>1 695:-large for some maximal 668:2-large and k-large sets 553:{\displaystyle k\cdot S} 50:This article includes a 687:is concerned only with 679:, for a natural number 584:is large, then for any 132:arithmetic progressions 79:more precise citations. 771:10.4153/cmb-1999-003-9 658: 598: 578: 554: 525: 420: 400: 399:{\displaystyle p(0)=0} 365: 345: 259: 122:is considered to be a 659: 599: 579: 555: 526: 421: 401: 371:is a polynomial with 366: 346: 295:contains n-cubes for 260: 706:-largeness implies ( 608: 588: 568: 538: 471: 410: 375: 355: 310: 198: 30:For other uses, see 716:-largeness for all 734:Partition of a set 720:implies largeness. 654: 594: 574: 550: 521: 416: 396: 361: 341: 255: 52:list of references 597:{\displaystyle m} 577:{\displaystyle S} 419:{\displaystyle S} 364:{\displaystyle p} 297:arbitrarily large 105: 104: 97: 16:(Redirected from 818: 775: 773: 663: 661: 660: 655: 650: 603: 601: 600: 595: 583: 581: 580: 575: 559: 557: 556: 551: 530: 528: 527: 522: 484: 457:is finite, then 425: 423: 422: 417: 405: 403: 402: 397: 370: 368: 367: 362: 350: 348: 347: 342: 340: 329: 264: 262: 261: 256: 245: 244: 232: 231: 219: 218: 100: 93: 89: 86: 80: 75:this article by 66:inline citations 45: 44: 37: 21: 826: 825: 821: 820: 819: 817: 816: 815: 791: 790: 782: 745: 742: 740:Further reading 730: 670: 606: 605: 586: 585: 566: 565: 536: 535: 534:If S is large, 469: 468: 408: 407: 373: 372: 353: 352: 308: 307: 278: 271: 236: 223: 210: 196: 195: 169: 152: 126:if and only if 120:natural numbers 101: 90: 84: 81: 70: 56:related reading 46: 42: 35: 28: 23: 22: 15: 12: 11: 5: 824: 822: 814: 813: 808: 803: 793: 792: 789: 788: 781: 780:External links 778: 777: 776: 748:Graham, Ronald 741: 738: 737: 736: 729: 726: 722: 721: 711: 669: 666: 653: 649: 646: 642: 639: 634: 631: 628: 625: 622: 619: 616: 613: 593: 573: 562: 561: 560:is also large. 549: 546: 543: 532: 520: 517: 514: 511: 508: 505: 502: 499: 496: 493: 490: 487: 483: 479: 476: 466: 428: 427: 415: 395: 392: 389: 386: 383: 380: 360: 339: 335: 332: 328: 324: 321: 318: 315: 304: 285: 284: 276: 269: 254: 251: 248: 243: 239: 235: 230: 226: 222: 217: 213: 209: 206: 203: 192: 168: 165: 164: 163: 160: 151: 148: 103: 102: 85:September 2015 60:external links 49: 47: 40: 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 823: 812: 809: 807: 806:Ramsey theory 804: 802: 799: 798: 796: 787: 784: 783: 779: 772: 767: 763: 759: 758: 753: 749: 744: 743: 739: 735: 732: 731: 727: 725: 719: 715: 712: 709: 705: 702: 701: 700: 698: 694: 690: 686: 682: 678: 676: 667: 665: 644: 640: 632: 629: 626: 623: 620: 614: 611: 591: 571: 547: 544: 541: 533: 515: 512: 509: 506: 503: 500: 497: 494: 491: 485: 477: 474: 467: 464: 462: 456: 453:is large and 452: 448: 447: 446: 443: 441: 437: 433: 413: 393: 390: 384: 378: 358: 333: 319: 316: 313: 305: 302: 298: 294: 290: 289: 288: 282: 275: 268: 249: 246: 241: 237: 233: 228: 224: 220: 215: 211: 204: 201: 193: 190: 186: 182: 178: 174: 173: 172: 166: 161: 158: 154: 153: 149: 147: 145: 141: 137: 133: 129: 125: 121: 117: 114: 110: 109:Ramsey theory 99: 96: 88: 78: 74: 68: 67: 61: 57: 53: 48: 39: 38: 33: 19: 764:(1): 25–36. 761: 755: 746:Brown, Tom; 723: 717: 713: 707: 703: 696: 692: 688: 680: 674: 673: 671: 563: 458: 454: 450: 444: 439: 431: 429: 300: 292: 286: 280: 273: 266: 188: 184: 180: 176: 170: 143: 139: 138:. That is, 135: 123: 115: 106: 91: 82: 71:Please help 63: 77:introducing 795:Categories 664:is large. 442:is large. 167:Properties 672:A set is 630:≡ 615:∩ 545:⋅ 531:is large. 516:… 478:⋅ 465:is large. 436:thick set 426:is large. 334:∩ 303:is large. 250:… 124:large set 728:See also 299:n, then 150:Examples 463: F 459:S  438:, then 73:improve 677:-large 351:where 434:is a 58:, or 283:≥ 2. 279:for 111:, a 766:doi 641:mod 564:If 449:If 306:If 291:If 277:k-1 194:If 175:If 118:of 113:set 107:In 797:: 762:42 760:. 754:. 604:, 272:≥3 183:, 146:. 62:, 54:, 774:. 768:: 718:k 714:k 708:k 704:k 697:k 693:k 689:k 681:k 675:k 652:} 648:) 645:m 638:( 633:0 627:x 624:: 621:x 618:{ 612:S 592:m 572:S 548:S 542:k 519:} 513:, 510:k 507:3 504:, 501:k 498:2 495:, 492:k 489:{ 486:= 482:N 475:k 461:– 455:F 451:S 440:S 432:S 414:S 394:0 391:= 388:) 385:0 382:( 379:p 359:p 338:N 331:) 327:N 323:( 320:p 317:= 314:S 301:S 293:S 281:k 274:s 270:k 267:s 253:} 247:, 242:3 238:s 234:, 229:2 225:s 221:, 216:1 212:s 208:{ 205:= 202:S 191:. 189:n 185:S 181:n 177:S 159:. 144:S 140:S 136:S 116:S 98:) 92:( 87:) 83:( 69:. 34:. 20:)

Index

Small set (Ramsey theory)
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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