Knowledge (XXG)

1/3–2/3 conjecture

Source πŸ“

20: 555:
to compare. Additionally, it may be possible to sort a partial order using a number of comparisons that is better than this analysis would suggest, because it may not be possible for this worst-case behavior to occur at each step of a sorting algorithm. In this direction, it has been conjectured that
532:
of elements may yield as little information as possible, by resolving the comparison in a way that leaves as many linear extensions as possible compatible with the comparison result. The 1/3–2/3 conjecture states that, at each step, one may choose a comparison to perform that reduces the remaining
292:
in the linear extension. In other words, it is a total order compatible with the partial order. If a finite partially ordered set is totally ordered, then it has only one linear extension, but otherwise it will have more than one. The 1/3–2/3 conjecture states that one can choose two elements
657:) for posets of width three is 14/39, and computer searches have shown that no smaller value is possible for width-3 posets with nine or fewer elements. Another related conjecture, again based on computer searches, states that there is a gap between 1/3 and the other possible values of Ξ΄( 44:
a set of items then, no matter what comparisons may have already been performed, it is always possible to choose the next comparison in such a way that it will reduce the number of possible sorted orders by a factor of 2/3 or better. Equivalently, in every finite
709:
If this conjecture is true, it would imply the 1/3–2/3 conjecture: the first of the two comparisons must be between a pair that splits the remaining comparisons by at worst a 1/3–2/3 ratio. The gold partition conjecture would also imply that a partial order with
27:
of one-element and three-element partial orders. Among its 27 linear extensions, the bottom left element occurs prior to the bottom right element in 9 out of 27. Partial orders with this structure are the only known extreme cases for the 1/3–2/3
331:
on the linear extensions in which each possible linear extension is equally likely to be chosen. The 1/3–2/3 conjecture states that, under this probability distribution, there exists a pair of elements
672:
Marcin Peczarski has formulated a "gold partition conjecture" stating that in each partial order that is not a total order one can find two consecutive comparisons such that, if
1594: 1565: 272:. A total order is a partial order in which every pair of elements is comparable. A linear extension of a finite partial order is a sequential ordering of the elements of 486:) to extend its definition to certain infinite partial orders; in that context, they show that their bounds are optimal, in that there exist infinite partial orders with 440:
two, partial orders of height two, partial orders with at most 11 elements, partial orders in which each element is incomparable to at most six others,
1833: 391:
of the total number of linear extensions. In this notation, the 1/3–2/3 conjecture states that every finite partial order that is not total has
570:
A closely related class of comparison sorting problems was considered by Fredman in 1976, among them the problem of comparison sorting a set
1239: 1720: 590:
is not necessarily generated as the set of linear extensions of a partial order. Despite this added generality, Fredman showed that
328: 641:
should tend to 1/2. In particular, they expect that only partially ordered sets of width two can achieve the worst case value
1129: 537:
linear extensions of the partial order given by the initial information, the sorting problem can be completed in at most log
441: 244:; they are the only known extreme cases for the conjecture and can be proven to be the only extreme cases with width two. 238: 218: 24: 1642: 1320: 1150:
Brightwell, Graham R.; Felsner, Stefan; Trotter, William T. (1995), "Balancing pairs and the cross product conjecture",
846:
to the problem of sorting partially ordered data and hence to the 1/3–2/3 conjecture, it is not mentioned in that paper.
356: 436:
The 1/3–2/3 conjecture is known to be true for certain special classes of partial orders, including partial orders of
425:, and remains unsolved; being called "one of the most intriguing problems in the combinatorial theory of posets." 1410: 1316: 1278: 509: 352: 482:
Their results improve previous weaker bounds of the same type. They use the probabilistic interpretation of Ξ΄(
233:
of elements, one of the two elements occurs earlier than the other in at most 1/3 of the linear extensions of
1161: 463:
In 1995, Graham Brightwell, Stefan Felsner, and William Trotter proved that, for any finite partial order
265: 1823: 46: 221:
of three-element partial orders and of one-element partial orders, such as the one in the figure. Then
1828: 1739: 1570: 1541: 1357:(1989), "Optimal algorithms in convex programming decomposition and sorting", in Jaravlev, J. (ed.), 1166: 685:
of the comparisons have been made, then (in each of the four possible outcomes of the comparisons)
269: 1802: 1776: 1755: 1729: 1702: 1668: 1631: 1605: 1526: 1501:
Peczarski, Marcin (2019), "The worst balanced partially ordered setsβ€”ladders with broken rungs",
1489: 1458: 1427: 1393: 1376: 1342: 1304: 1222: 1187: 1115: 1084: 324: 261: 721:
comparisons; the name of the conjecture is derived from this connection with the golden ratio.
1767:
Zaguia, Imed (2019), "The 1/3–2/3 conjecture for ordered sets whose cover graph is a forest",
1680: 520:, for which some partial order information is already known in the form of a partial order on 323:
There is an alternative and equivalent statement of the 1/3–2/3 conjecture in the language of
1786: 1747: 1694: 1660: 1615: 1510: 1481: 1450: 1419: 1385: 1371: 1354: 1334: 1296: 1267: 1214: 1171: 1138: 1107: 1076: 725: 408: 62: 1798: 1627: 1522: 1247: 1183: 301:
such that, among this set of possible linear extensions, between 1/3 and 2/3 of them place
1794: 1685: 1651: 1623: 1518: 1472: 1441: 1325: 1255: 1243: 1234:
Felsner, Stefan; Trotter, William T. (1993), "Balancing pairs in partially ordered sets",
1205: 1179: 1152: 1098: 1067: 513: 421: 412: 257: 41: 176:
have the desired property, showing that this partial order obeys the 1/3–2/3 conjecture.
1743: 1646: 1062: 607: 1142: 1817: 1806: 1672: 1635: 1530: 1397: 1346: 1308: 1287: 1271: 1226: 1200: 1088: 1058: 650: 419:
in 1984. It was listed as a featured unsolved problem at the founding of the journal
1706: 1493: 1462: 1374:(1968), "A finite partially ordered set and its corresponding set of permutations", 1191: 1119: 1759: 1431: 564: 512:
and Saks proposed the following application for the problem: suppose one wishes to
33: 1514: 610:. This same bound applies as well to the case of partial orders and shows that log 225:
forms an extreme case for the 1/3–2/3 conjecture in the sense that, for each pair
179:
This example shows that the constants 1/3 and 2/3 in the conjecture are tight; if
1405: 1282: 416: 183:
is any fraction strictly between 1/3 and 2/3, then there would not exist a pair
50: 1790: 1619: 1485: 1454: 1470:
Peczarski, Marcin (2008), "The gold partition conjecture for 6-thin posets",
547:
However, this analysis neglects the complexity of selecting the optimal pair
445: 437: 241: 460:-element partial orders that obey the 1/3–2/3 conjecture approaches 100%. 19: 449: 533:
number of linear extensions by a factor of 2/3; therefore, if there are
1698: 1664: 1389: 1338: 1300: 1218: 1175: 1111: 1096:
Brightwell, Graham R. (1989), "Semiorders and the 1/3–2/3 conjecture",
1080: 801: 799: 797: 795: 653:
stated this explicitly as a conjecture. The smallest known value of Ξ΄(
881: 879: 1423: 1781: 1610: 1751: 1734: 1127:
Brightwell, Graham R. (1999), "Balanced pairs in partial orders",
18: 1258:(1976), "How good is the information theory bound in sorting?", 1408:(1984), "The information-theoretic bound is good for merging", 524:. In the worst case, each additional comparison between a pair 1238:, Bolyai Society Mathematical Studies, vol. 1, Budapest: 1439:
Peczarski, Marcin (2006), "The gold partition conjecture",
61:
with the property that at least 1/3 and at most 2/3 of the
740:, to calculate the proportion of the linear extensions of 629:
In 1984, Kahn and Saks conjectured that, in the limit as
1364: 967: 805: 771: 681:
denotes the number of linear extensions remaining after
885: 387:
in a number of linear extensions that is between Ξ΄ and
1575: 1546: 309:, and symmetrically between 1/3 and 2/3 of them place 1573: 1544: 348:
in a random linear extension is between 1/3 and 2/3.
237:. Partial orders with this structure are necessarily 1285:(1991), "Balancing extensions via Brunn-Minkowski", 782: 780: 1588: 1559: 1714:Zaguia, Imed (2012), "The 1/3-2/3 Conjecture for 1042: 428:A survey of the conjecture was produced in 1999. 199:in a number of partial orderings that is between 1683:(1992), "Balance theorems for height-2 posets", 983: 714:linear extensions can be sorted in at most log 1647:"Balancing linear extensions of ordered sets" 1361:(in Russian), Moscow: Nauka, pp. 161–205 563:comparisons may suffice, where Ο† denotes the 210:times the total number of partial orderings. 8: 661:): whenever a partial order does not have Ξ΄( 367:, to be the largest real number Ξ΄ such that 1679:Trotter, William T.; Gehrlein, William V.; 816: 814: 81:The partial order formed by three elements 979: 943: 855: 93:with a single comparability relationship, 1780: 1733: 1609: 1574: 1572: 1545: 1543: 1165: 1030: 975: 919: 904: 842:However, despite the close connection of 831: 411:in 1968, and later made independently by 407:The 1/3–2/3 conjecture was formulated by 1365:Brightwell, Felsner & Trotter (1995) 1006: 971: 968:Brightwell, Felsner & Trotter (1995) 820: 806:Brightwell, Felsner & Trotter (1995) 772:Brightwell, Felsner & Trotter (1995) 767: 995: 886:Trotter, Gehrlein & Fishburn (1992) 843: 760: 1323:(1984), "Balancing poset extensions", 1203:(1991), "Counting linear extensions", 955: 931: 915: 913: 900: 898: 896: 894: 866: 786: 637:) for partially ordered sets of width 168:in the third. Therefore, the pair of 7: 1018: 456:goes to infinity, the proportion of 164:in only two of them, and later than 1721:Electronic Journal of Combinatorics 1538:Sah, Ashwin (2021), "Improving the 1236:Combinatorics, Paul ErdΕ‘s is eighty 870: 625:Generalizations and related results 1596:conjecture for width two posets", 633:tends to infinity, the value of Ξ΄( 148:In all three of these extensions, 53:, there exists a pair of elements 16:Unsolved problem on partial orders 14: 1240:JΓ‘nos Bolyai Mathematical Society 363:), for any partially ordered set 252:A partially ordered set is a set 1834:Unsolved problems in mathematics 728:, given a finite partial order 329:uniform probability distribution 1589:{\displaystyle {\tfrac {2}{3}}} 1560:{\displaystyle {\tfrac {1}{3}}} 1359:Computers and Decision Problems 1043:Brightwell & Winkler (1991) 340:such that the probability that 36:, a branch of mathematics, the 442:series-parallel partial orders 23:A partial order formed by the 1: 1515:10.1080/10586458.2017.1368050 1143:10.1016/S0012-365X(98)00311-2 606:|) comparisons, expressed in 104:has three linear extensions, 1272:10.1016/0304-3975(76)90078-5 1260:Theoretical Computer Science 984:Felsner & Trotter (1993) 578:is known to lie in some set 276:, with the property that if 284:in the partial order, then 65:of the partial order place 1850: 1791:10.1007/s11083-018-9469-0 1620:10.1007/s00493-020-4091-3 1486:10.1007/s11083-008-9081-9 1455:10.1007/s11083-006-9033-1 1411:SIAM Journal on Computing 574:when the sorted order of 1503:Experimental Mathematics 980:Kahn & Linial (1991) 665:) exactly 1/3, it has Ξ΄( 544:additional comparisons. 1199:Brightwell, Graham R.; 732:and a pair of elements 621:) comparisons suffice. 594:can be sorted using log 40:states that, if one is 1590: 1561: 1007:Kahn & Saks (1984) 972:Kahn & Saks (1984) 821:Kahn & Saks (1984) 768:Kahn & Saks (1984) 516:a totally ordered set 29: 1718:-free ordered sets", 1649:, Unsolved problems, 1591: 1562: 47:partially ordered set 22: 1571: 1542: 1242:, pp. 145–157, 1130:Discrete Mathematics 213:More generally, let 1744:2011arXiv1107.5626Z 1063:"A note on merging" 582:of permutations of 467:that is not total, 327:. One may define a 1699:10.1007/BF00419038 1681:Fishburn, Peter C. 1665:10.1007/BF00333138 1586: 1584: 1557: 1555: 1390:10.1007/BF01111312 1377:Mathematical Notes 1339:10.1007/BF00565647 1301:10.1007/BF01275670 1219:10.1007/BF00383444 1176:10.1007/BF01110378 1112:10.1007/BF00353656 1081:10.1007/BF00333131 452:. In the limit as 325:probability theory 219:series composition 42:comparison sorting 38:1/3–2/3 conjecture 30: 25:series composition 1583: 1554: 1355:Khachiyan, Leonid 944:Brightwell (1989) 856:Brightwell (1999) 602:| + O(| 288:must come before 63:linear extensions 1841: 1809: 1784: 1762: 1737: 1709: 1675: 1638: 1613: 1595: 1593: 1592: 1587: 1585: 1576: 1566: 1564: 1563: 1558: 1556: 1547: 1533: 1496: 1465: 1434: 1400: 1372:Kislitsyn, S. S. 1362: 1349: 1311: 1274: 1250: 1229: 1194: 1169: 1145: 1122: 1091: 1046: 1040: 1034: 1031:Peczarski (2019) 1028: 1022: 1016: 1010: 1004: 998: 993: 987: 976:Khachiyan (1989) 965: 959: 953: 947: 941: 935: 929: 923: 920:Peczarski (2008) 917: 908: 905:Peczarski (2006) 902: 889: 883: 874: 864: 858: 853: 847: 840: 834: 832:Kislitsyn (1968) 829: 823: 818: 809: 803: 790: 784: 775: 765: 708: 648: 500: 498: 497: 492:) = 1/2 − 481: 479: 478: 473:) β‰₯ 1/2 − 409:Sergey Kislitsyn 398: 390: 344:is earlier than 320: 256:together with a 209: 195:is earlier than 160:is earlier than 152:is earlier than 147: 132: 118: 103: 1849: 1848: 1844: 1843: 1842: 1840: 1839: 1838: 1814: 1813: 1766: 1713: 1678: 1641: 1569: 1568: 1540: 1539: 1537: 1500: 1469: 1438: 1424:10.1137/0213049 1404: 1370: 1353: 1315: 1277: 1254: 1233: 1198: 1149: 1126: 1095: 1057: 1054: 1049: 1041: 1037: 1029: 1025: 1017: 1013: 1005: 1001: 994: 990: 966: 962: 954: 950: 942: 938: 930: 926: 918: 911: 903: 892: 884: 877: 865: 861: 854: 850: 841: 837: 830: 826: 819: 812: 804: 793: 785: 778: 766: 762: 758: 717: 706: 699: 692: 686: 680: 642: 627: 617: + O( 613: 597: 559: 540: 514:comparison sort 506: 495: 493: 487: 476: 474: 468: 434: 432:Partial results 413:Michael Fredman 405: 392: 388: 314: 258:binary relation 250: 239:series-parallel 204: 134: 119: 105: 94: 79: 51:totally ordered 17: 12: 11: 5: 1847: 1845: 1837: 1836: 1831: 1826: 1816: 1815: 1812: 1811: 1775:(2): 335–347, 1764: 1711: 1676: 1639: 1582: 1579: 1553: 1550: 1535: 1509:(2): 181–184, 1498: 1467: 1436: 1418:(4): 795–801, 1402: 1384:(5): 798–801, 1368: 1363:. As cited by 1351: 1333:(2): 113–126, 1313: 1295:(4): 363–368, 1275: 1266:(4): 355–361, 1256:Fredman, M. L. 1252: 1231: 1213:(3): 225–242, 1201:Winkler, Peter 1196: 1167:10.1.1.38.7841 1160:(4): 327–349, 1147: 1137:(1–3): 25–52, 1124: 1106:(4): 369–380, 1093: 1075:(3): 257–264, 1059:Aigner, Martin 1053: 1050: 1048: 1047: 1035: 1023: 1011: 999: 996:Fredman (1976) 988: 960: 948: 936: 924: 909: 890: 875: 859: 848: 844:Fredman (1976) 835: 824: 810: 791: 776: 759: 757: 754: 715: 704: 697: 690: 676: 669:) β‰₯ 0.348843. 626: 623: 611: 608:big O notation 595: 557: 538: 505: 502: 433: 430: 404: 401: 249: 246: 78: 75: 15: 13: 10: 9: 6: 4: 3: 2: 1846: 1835: 1832: 1830: 1827: 1825: 1822: 1821: 1819: 1808: 1804: 1800: 1796: 1792: 1788: 1783: 1778: 1774: 1770: 1765: 1761: 1757: 1753: 1752:10.37236/2345 1749: 1745: 1741: 1736: 1731: 1727: 1723: 1722: 1717: 1712: 1708: 1704: 1700: 1696: 1692: 1688: 1687: 1682: 1677: 1674: 1670: 1666: 1662: 1658: 1654: 1653: 1648: 1644: 1643:Saks, Michael 1640: 1637: 1633: 1629: 1625: 1621: 1617: 1612: 1607: 1604:(1): 99–126, 1603: 1599: 1598:Combinatorica 1580: 1577: 1551: 1548: 1536: 1532: 1528: 1524: 1520: 1516: 1512: 1508: 1504: 1499: 1495: 1491: 1487: 1483: 1480:(2): 91–103, 1479: 1475: 1474: 1468: 1464: 1460: 1456: 1452: 1448: 1444: 1443: 1437: 1433: 1429: 1425: 1421: 1417: 1413: 1412: 1407: 1403: 1399: 1395: 1391: 1387: 1383: 1379: 1378: 1373: 1369: 1366: 1360: 1356: 1352: 1348: 1344: 1340: 1336: 1332: 1328: 1327: 1322: 1321:Saks, Michael 1318: 1314: 1310: 1306: 1302: 1298: 1294: 1290: 1289: 1288:Combinatorica 1284: 1280: 1276: 1273: 1269: 1265: 1261: 1257: 1253: 1249: 1245: 1241: 1237: 1232: 1228: 1224: 1220: 1216: 1212: 1208: 1207: 1202: 1197: 1193: 1189: 1185: 1181: 1177: 1173: 1168: 1163: 1159: 1155: 1154: 1148: 1144: 1140: 1136: 1132: 1131: 1125: 1121: 1117: 1113: 1109: 1105: 1101: 1100: 1094: 1090: 1086: 1082: 1078: 1074: 1070: 1069: 1064: 1060: 1056: 1055: 1051: 1044: 1039: 1036: 1032: 1027: 1024: 1020: 1015: 1012: 1008: 1003: 1000: 997: 992: 989: 985: 981: 977: 973: 969: 964: 961: 957: 956:Zaguia (2019) 952: 949: 945: 940: 937: 933: 932:Zaguia (2012) 928: 925: 921: 916: 914: 910: 906: 901: 899: 897: 895: 891: 887: 882: 880: 876: 872: 869:, Theorem 2; 868: 867:Linial (1984) 863: 860: 857: 852: 849: 845: 839: 836: 833: 828: 825: 822: 817: 815: 811: 807: 802: 800: 798: 796: 792: 788: 787:Aigner (1985) 783: 781: 777: 773: 769: 764: 761: 755: 753: 751: 748:earlier than 747: 743: 739: 735: 731: 727: 722: 720: 713: 703: 696: 689: 684: 679: 675: 670: 668: 664: 660: 656: 652: 651:Martin Aigner 646: 640: 636: 632: 624: 622: 620: 616: 609: 605: 601: 593: 589: 585: 581: 577: 573: 568: 566: 562: 554: 550: 545: 543: 536: 531: 527: 523: 519: 515: 511: 503: 501: 491: 485: 472: 466: 461: 459: 455: 451: 447: 443: 439: 431: 429: 426: 424: 423: 418: 414: 410: 402: 400: 396: 386: 383:earlier than 382: 378: 374: 370: 366: 362: 358: 354: 349: 347: 343: 339: 335: 330: 326: 321: 318: 312: 308: 305:earlier than 304: 300: 296: 291: 287: 283: 279: 275: 271: 267: 266:antisymmetric 263: 259: 255: 247: 245: 243: 240: 236: 232: 228: 224: 220: 216: 211: 208: 202: 198: 194: 190: 186: 182: 177: 175: 171: 167: 163: 159: 155: 151: 145: 141: 137: 130: 126: 122: 116: 112: 108: 101: 97: 92: 88: 84: 76: 74: 72: 69:earlier than 68: 64: 60: 56: 52: 48: 43: 39: 35: 26: 21: 1824:Order theory 1772: 1768: 1725: 1719: 1715: 1693:(1): 43–53, 1690: 1684: 1656: 1650: 1601: 1597: 1506: 1502: 1477: 1471: 1449:(1): 89–95, 1446: 1440: 1415: 1409: 1406:Linial, Nati 1381: 1375: 1358: 1330: 1324: 1292: 1286: 1283:Linial, Nati 1263: 1259: 1235: 1210: 1204: 1157: 1151: 1134: 1128: 1103: 1097: 1072: 1066: 1038: 1026: 1014: 1002: 991: 963: 951: 939: 927: 862: 851: 838: 827: 763: 749: 745: 741: 737: 733: 729: 723: 718: 711: 701: 694: 687: 682: 677: 673: 671: 666: 662: 658: 654: 649:and in 1985 644: 638: 634: 630: 628: 618: 614: 603: 599: 591: 587: 583: 579: 575: 571: 569: 565:golden ratio 560: 552: 548: 546: 541: 534: 529: 525: 521: 517: 507: 504:Applications 489: 483: 480:/10 β‰ˆ 0.276. 470: 464: 462: 457: 453: 435: 427: 420: 406: 394: 384: 380: 376: 372: 368: 364: 360: 357:Michael Saks 350: 345: 341: 337: 333: 322: 316: 310: 306: 302: 298: 294: 289: 285: 281: 277: 273: 253: 251: 234: 230: 226: 222: 214: 212: 206: 200: 196: 192: 188: 184: 180: 178: 173: 169: 165: 161: 157: 153: 149: 143: 139: 135: 128: 124: 120: 114: 110: 106: 99: 95: 90: 86: 82: 80: 70: 66: 58: 54: 49:that is not 37: 34:order theory 31: 1829:Conjectures 1659:: 327–330, 1019:Saks (1985) 744:that place 726:#P-complete 417:Nati Linial 389:1 − Ξ΄ 371:has a pair 248:Definitions 156:. However, 28:conjecture. 1818:Categories 1782:1610.00809 1728:(2): P29, 1611:1811.01500 1317:Kahn, Jeff 1279:Kahn, Jeff 1052:References 871:Sah (2021) 446:semiorders 359:defined Ξ΄( 270:transitive 260:≀ that is 242:semiorders 205:1 − 1807:119631612 1735:1107.5626 1673:189901558 1636:119604901 1531:125593629 1398:120228193 1347:123370506 1309:206793172 1227:119697949 1162:CiteSeerX 1089:118877843 510:Jeff Kahn 450:polytrees 353:Jeff Kahn 351:In 1984, 262:reflexive 191:in which 1707:16157076 1645:(1985), 1494:42034095 1463:42415160 1192:14793475 1120:86860160 1061:(1985), 647:) = 1/3, 508:In 1984 313:earlier 1799:3983482 1760:1979845 1740:Bibcode 1628:4235316 1523:3955809 1432:5149351 1248:1249709 1184:1368815 586:. Here 494:√ 475:√ 415:and by 403:History 397:) β‰₯ 1/3 217:be any 77:Example 1805:  1797:  1758:  1705:  1671:  1634:  1626:  1529:  1521:  1492:  1461:  1430:  1396:  1345:  1307:  1246:  1225:  1190:  1182:  1164:  1118:  1087:  724:It is 448:. and 268:, and 89:, and 1803:S2CID 1777:arXiv 1769:Order 1756:S2CID 1730:arXiv 1703:S2CID 1686:Order 1669:S2CID 1652:Order 1632:S2CID 1606:arXiv 1527:S2CID 1490:S2CID 1473:Order 1459:S2CID 1442:Order 1428:S2CID 1394:S2CID 1343:S2CID 1326:Order 1305:S2CID 1223:S2CID 1206:Order 1188:S2CID 1153:Order 1116:S2CID 1099:Order 1085:S2CID 1068:Order 756:Notes 438:width 422:Order 379:with 315:than 736:and 551:and 528:and 499:/10. 355:and 336:and 297:and 203:and 172:and 133:and 57:and 1787:doi 1748:doi 1695:doi 1661:doi 1616:doi 1511:doi 1482:doi 1451:doi 1420:doi 1386:doi 1335:doi 1297:doi 1268:doi 1215:doi 1172:doi 1139:doi 1135:201 1108:doi 1077:doi 556:log 539:3/2 32:In 1820:: 1801:, 1795:MR 1793:, 1785:, 1773:36 1771:, 1754:, 1746:, 1738:, 1726:19 1724:, 1701:, 1689:, 1667:, 1655:, 1630:, 1624:MR 1622:, 1614:, 1602:41 1600:, 1525:, 1519:MR 1517:, 1507:28 1505:, 1488:, 1478:25 1476:, 1457:, 1447:23 1445:, 1426:, 1416:13 1414:, 1392:, 1380:, 1341:, 1329:, 1319:; 1303:, 1293:11 1291:, 1281:; 1262:, 1244:MR 1221:, 1209:, 1186:, 1180:MR 1178:, 1170:, 1158:12 1156:, 1133:, 1114:, 1102:, 1083:, 1071:, 1065:, 982:; 978:; 974:; 970:; 912:^ 893:^ 878:^ 813:^ 794:^ 779:^ 770:; 752:. 700:+ 693:β‰₯ 643:Ξ΄( 567:. 488:Ξ΄( 469:Ξ΄( 444:, 399:. 393:Ξ΄( 375:, 280:≀ 264:, 229:, 187:, 142:≀ 138:≀ 127:≀ 123:≀ 113:≀ 109:≀ 98:≀ 85:, 73:. 1810:. 1789:: 1779:: 1763:. 1750:: 1742:: 1732:: 1716:N 1710:. 1697:: 1691:9 1663:: 1657:2 1618:: 1608:: 1581:3 1578:2 1567:– 1552:3 1549:1 1534:. 1513:: 1497:. 1484:: 1466:. 1453:: 1435:. 1422:: 1401:. 1388:: 1382:4 1367:. 1350:. 1337:: 1331:1 1312:. 1299:: 1270:: 1264:1 1251:. 1230:. 1217:: 1211:8 1195:. 1174:: 1146:. 1141:: 1123:. 1110:: 1104:5 1092:. 1079:: 1073:2 1045:. 1033:. 1021:. 1009:. 986:. 958:. 946:. 934:. 922:. 907:. 888:. 873:. 808:. 789:. 774:. 750:y 746:x 742:P 738:y 734:x 730:P 719:E 716:Ο† 712:E 707:. 705:2 702:t 698:1 695:t 691:0 688:t 683:i 678:i 674:t 667:P 663:P 659:P 655:P 645:P 639:w 635:P 631:w 619:n 615:E 612:2 604:X 600:S 598:| 596:2 592:X 588:S 584:X 580:S 576:X 572:X 561:E 558:Ο† 553:y 549:x 542:E 535:E 530:y 526:x 522:X 518:X 496:5 490:P 484:P 477:5 471:P 465:P 458:n 454:n 395:P 385:y 381:x 377:y 373:x 369:P 365:P 361:P 346:y 342:x 338:y 334:x 319:. 317:x 311:y 307:y 303:x 299:y 295:x 290:y 286:x 282:y 278:x 274:X 254:X 235:P 231:y 227:x 223:P 215:P 207:q 201:q 197:y 193:x 189:y 185:x 181:q 174:c 170:a 166:c 162:c 158:a 154:b 150:a 146:. 144:b 140:a 136:c 131:, 129:b 125:c 121:a 117:, 115:c 111:b 107:a 102:, 100:b 96:a 91:c 87:b 83:a 71:y 67:x 59:y 55:x

Index


series composition
order theory
comparison sorting
partially ordered set
totally ordered
linear extensions
series composition
series-parallel
semiorders
binary relation
reflexive
antisymmetric
transitive
probability theory
uniform probability distribution
Jeff Kahn
Michael Saks
Sergey Kislitsyn
Michael Fredman
Nati Linial
Order
width
series-parallel partial orders
semiorders
polytrees
Jeff Kahn
comparison sort
golden ratio
big O notation

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

↑