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Kleene fixed-point theorem

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27: 339: 450: 2162: 699: 1100: 1861: 945: 1316: 776: 1422: 1499: 1009: 863: 251: 1944: 2294: 1371: 2026: 130: 477: 365: 1673: 1623: 1125: 614: 166: 2243: 1722: 1534: 1226: 1964: 1893: 1442: 796: 2205: 1148: 229: 2182: 2066: 2046: 1984: 1802: 1782: 1762: 1742: 1693: 1643: 1597: 1574: 1554: 1246: 1191: 1168: 582: 555: 535: 198: 2071: 619: 1023: 1807: 868: 1255: 714: 1376: 483: 19:
This article is about Kleene's fixed-point theorem in lattice theory. For the fixed-point theorem in computability theory, see
1447: 334:{\displaystyle \bot \sqsubseteq f(\bot )\sqsubseteq f(f(\bot ))\sqsubseteq \cdots \sqsubseteq f^{n}(\bot )\sqsubseteq \cdots } 2395: 950: 804: 2422: 20: 1898: 2248: 1321: 1989: 177: 133: 66: 2326: 2417: 445:{\displaystyle {\textrm {lfp}}(f)=\sup \left(\left\{f^{n}(\bot )\mid n\in \mathbb {N} \right\}\right)} 103: 458: 243: 1011:
holds, and because f is monotone (property of Scott-continuous functions), the result holds as well.
2305: 90: 1652: 1606: 1108: 2379: 2373: 2391: 587: 503: 502:
who proves it for additive functions. Moreover, Kleene Fixed-Point Theorem can be extended to
495: 491: 345: 201: 173: 139: 2210: 1698: 2383: 1504: 1249: 1196: 169: 1949: 1866: 1427: 781: 2187: 1130: 211: 2167: 2051: 2031: 1969: 1787: 1767: 1747: 1727: 1678: 1628: 1582: 1559: 1539: 1231: 1176: 1153: 567: 540: 520: 183: 82: 2028:. We now do the induction step: From the induction hypothesis and the monotonicity of 2411: 499: 352: 2157:{\displaystyle f^{i}(\bot )\sqsubseteq k~\implies ~f^{i+1}(\bot )\sqsubseteq f(k).} 78: 26: 2350: 74: 58: 2387: 694:{\displaystyle f^{n}(\bot )\sqsubseteq f^{n+1}(\bot ),n\in \mathbb {N} _{0}} 1646: 205: 1095:{\displaystyle \mathbb {M} =\{\bot ,f(\bot ),f(f(\bot )),\ldots \}.} 1017:
As a corollary of the Lemma we have the following directed ω-chain:
1856:{\displaystyle \forall i\in \mathbb {N} :f^{i}(\bot )\sqsubseteq k} 25: 486:
does not consider how fixed points can be computed by iterating
2372:
Stoltenberg-Hansen, V.; Lindstrom, I.; Griffor, E. R. (1994).
2327:"A lattice-theoretical fixpoint theorem and its applications" 940:{\displaystyle f(f^{n-1}(\bot ))\sqsubseteq f(f^{n}(\bot ))} 1311:{\displaystyle f(\sup(\mathbb {M} ))=\sup(f(\mathbb {M} ))} 771:{\displaystyle f^{0}(\bot )=\bot \sqsubseteq f^{1}(\bot ),} 1417:{\displaystyle \mathbb {M} =f(\mathbb {M} )\cup \{\bot \}} 517:
We first have to show that the ascending Kleene chain of
2351:"Constructive versions of Tarski's fixed point theorems" 1494:{\displaystyle \sup(f(\mathbb {M} ))=\sup(\mathbb {M} )} 2375:
Mathematical Theory of Domains by V. Stoltenberg-Hansen
1603:
fixed point can be done by showing that any element in
1444:
has no influence in determining the supremum we have:
1004:{\displaystyle f^{n-1}(\bot )\sqsubseteq f^{n}(\bot )} 858:{\displaystyle f^{n}(\bot )\sqsubseteq f^{n+1}(\bot )} 2251: 2213: 2190: 2170: 2074: 2054: 2034: 1992: 1972: 1952: 1901: 1869: 1810: 1790: 1770: 1750: 1730: 1701: 1681: 1655: 1631: 1609: 1585: 1562: 1542: 1507: 1450: 1430: 1379: 1324: 1258: 1234: 1199: 1179: 1156: 1133: 1111: 1026: 953: 871: 807: 784: 717: 622: 590: 570: 543: 523: 461: 368: 254: 214: 186: 142: 106: 2288: 2237: 2199: 2176: 2156: 2060: 2040: 2020: 1986:. As the induction hypothesis, we may assume that 1978: 1958: 1938: 1887: 1855: 1796: 1776: 1756: 1736: 1716: 1687: 1667: 1637: 1617: 1591: 1568: 1548: 1528: 1493: 1436: 1416: 1365: 1310: 1240: 1220: 1185: 1162: 1142: 1119: 1094: 1003: 939: 857: 790: 770: 693: 608: 576: 549: 529: 471: 444: 359:. Expressed in a formula, the theorem states that 333: 223: 192: 160: 124: 1939:{\displaystyle f^{0}(\bot )=\bot \sqsubseteq k,} 1702: 1477: 1451: 1340: 1285: 1265: 388: 1105:From the definition of a dcpo it follows that 8: 2289:{\displaystyle f^{i+1}(\bot )\sqsubseteq k.} 1411: 1405: 1086: 1035: 2048:(again, implied by the Scott-continuity of 801:Assume n > 0. Then we have to show that 2107: 2103: 1366:{\displaystyle f(m)=\sup(f(\mathbb {M} ))} 16:Theorem in order theory and lattice theory 2349:Patrick Cousot and Radhia Cousot (1979). 2256: 2250: 2212: 2189: 2169: 2115: 2079: 2073: 2053: 2033: 2021:{\displaystyle f^{i}(\bot )\sqsubseteq k} 1997: 1991: 1971: 1951: 1906: 1900: 1868: 1832: 1821: 1820: 1809: 1789: 1769: 1749: 1729: 1700: 1680: 1654: 1630: 1611: 1610: 1608: 1584: 1561: 1541: 1506: 1484: 1483: 1464: 1463: 1449: 1429: 1395: 1394: 1381: 1380: 1378: 1353: 1352: 1323: 1298: 1297: 1272: 1271: 1257: 1233: 1198: 1178: 1155: 1132: 1113: 1112: 1110: 1028: 1027: 1025: 986: 958: 952: 919: 882: 870: 834: 812: 806: 783: 750: 722: 716: 685: 681: 680: 649: 627: 621: 589: 569: 542: 522: 463: 462: 460: 429: 428: 404: 370: 369: 367: 310: 253: 213: 185: 141: 105: 947:. By inductive assumption, we know that 557:. To show that, we prove the following: 2378:. Cambridge University Press. pp.  2317: 65:)+1 using Kleene's theorem in the real 498:), this result is often attributed to 490:from some seed (also, it pertains to 1744:). This is done by induction: Assume 1724:is smaller than that same element of 136:(dcpo) with a least element, and let 89:, named after American mathematician 30:Computation of the least fixpoint of 7: 584:is a dcpo with a least element, and 1625:is smaller than any fixed-point of 2271: 2130: 2088: 2068:), we may conclude the following: 2006: 1953: 1924: 1915: 1841: 1811: 1431: 1408: 1071: 1050: 1038: 995: 973: 928: 897: 849: 821: 785: 759: 740: 731: 664: 636: 413: 319: 288: 267: 255: 14: 1784:. We now prove by induction over 1150:What remains now is to show that 208:of the ascending Kleene chain of 125:{\displaystyle (L,\sqsubseteq )} 1675:are smaller than an element of 479:denotes the least fixed point. 472:{\displaystyle {\textrm {lfp}}} 134:directed-complete partial order 2355:Pacific Journal of Mathematics 2331:Pacific Journal of Mathematics 2274: 2268: 2223: 2217: 2148: 2142: 2133: 2127: 2104: 2091: 2085: 2009: 2003: 1918: 1912: 1882: 1870: 1844: 1838: 1711: 1705: 1517: 1511: 1488: 1480: 1471: 1468: 1460: 1454: 1399: 1391: 1360: 1357: 1349: 1343: 1334: 1328: 1305: 1302: 1294: 1288: 1279: 1276: 1268: 1262: 1209: 1203: 1077: 1074: 1068: 1062: 1053: 1047: 998: 992: 976: 970: 934: 931: 925: 912: 903: 900: 894: 875: 852: 846: 824: 818: 762: 756: 734: 728: 667: 661: 639: 633: 600: 506:using transfinite iterations. 416: 410: 382: 376: 322: 316: 294: 291: 285: 279: 270: 264: 152: 119: 107: 1: 2164:Now, by the assumption that 1863:. The base of the induction 1668:{\displaystyle D\subseteq L} 1618:{\displaystyle \mathbb {M} } 1193:is a fixed point, i.e. that 1120:{\displaystyle \mathbb {M} } 484:Tarski's fixed point theorem 1649:, if all elements of a set 98:Kleene Fixed-Point Theorem. 2439: 1170:is the least fixed-point. 616:is Scott-continuous, then 87:Kleene fixed-point theorem 21:Kleene's recursion theorem 18: 2388:10.1017/cbo9781139166386 1966:is the least element of 1645:(because by property of 1127:has a supremum, call it 865:. By rearranging we get 609:{\displaystyle f:L\to L} 161:{\displaystyle f:L\to L} 93:, states the following: 2238:{\displaystyle f(k)=k,} 1764:is some fixed-point of 1717:{\displaystyle \sup(D)} 2325:Alfred Tarski (1955). 2290: 2239: 2201: 2178: 2158: 2062: 2042: 2022: 1980: 1960: 1940: 1889: 1857: 1798: 1778: 1758: 1738: 1718: 1689: 1669: 1639: 1619: 1593: 1570: 1550: 1530: 1529:{\displaystyle f(m)=m} 1495: 1438: 1418: 1367: 1312: 1242: 1222: 1221:{\displaystyle f(m)=m} 1187: 1164: 1144: 1121: 1096: 1005: 941: 859: 792: 772: 695: 610: 578: 551: 531: 473: 446: 335: 236:ascending Kleene chain 225: 194: 162: 126: 70: 2291: 2245:and from that we get 2240: 2202: 2179: 2159: 2063: 2043: 2023: 1981: 1961: 1959:{\displaystyle \bot } 1941: 1890: 1888:{\displaystyle (i=0)} 1858: 1799: 1779: 1759: 1739: 1719: 1690: 1670: 1640: 1620: 1594: 1571: 1551: 1531: 1496: 1439: 1437:{\displaystyle \bot } 1419: 1368: 1313: 1243: 1223: 1188: 1165: 1145: 1122: 1097: 1006: 942: 860: 798:is the least element. 793: 791:{\displaystyle \bot } 773: 696: 611: 579: 552: 532: 474: 447: 336: 226: 195: 163: 127: 29: 2423:Fixed-point theorems 2306:fixed-point theorems 2249: 2211: 2188: 2184:is a fixed-point of 2168: 2072: 2052: 2032: 1990: 1970: 1950: 1899: 1867: 1808: 1788: 1768: 1748: 1728: 1699: 1679: 1653: 1629: 1607: 1583: 1560: 1540: 1505: 1448: 1428: 1377: 1322: 1256: 1232: 1197: 1177: 1173:First, we show that 1154: 1131: 1109: 1024: 951: 869: 805: 782: 715: 620: 588: 568: 541: 521: 459: 366: 252: 212: 184: 140: 104: 69:with the usual order 711:Assume n = 0. Then 91:Stephen Cole Kleene 2286: 2235: 2200:{\displaystyle f,} 2197: 2174: 2154: 2058: 2038: 2018: 1976: 1956: 1936: 1885: 1853: 1794: 1774: 1754: 1734: 1714: 1685: 1665: 1635: 1615: 1589: 1566: 1546: 1526: 1501:. It follows that 1491: 1434: 1414: 1363: 1308: 1238: 1218: 1183: 1160: 1143:{\displaystyle m.} 1140: 1117: 1092: 1001: 937: 855: 788: 768: 708:We use induction: 691: 606: 574: 547: 527: 504:monotone functions 492:monotone functions 469: 442: 331: 224:{\displaystyle f.} 221: 190: 158: 122: 71: 2177:{\displaystyle k} 2110: 2102: 2061:{\displaystyle f} 2041:{\displaystyle f} 1979:{\displaystyle L} 1895:obviously holds: 1797:{\displaystyle i} 1777:{\displaystyle f} 1757:{\displaystyle k} 1737:{\displaystyle L} 1688:{\displaystyle L} 1638:{\displaystyle f} 1592:{\displaystyle m} 1569:{\displaystyle f} 1556:a fixed-point of 1549:{\displaystyle m} 1241:{\displaystyle f} 1186:{\displaystyle m} 1163:{\displaystyle m} 577:{\displaystyle L} 550:{\displaystyle L} 530:{\displaystyle f} 496:complete lattices 466: 373: 202:least fixed point 193:{\displaystyle f} 2430: 2402: 2401: 2369: 2363: 2362: 2346: 2340: 2338: 2322: 2295: 2293: 2292: 2287: 2267: 2266: 2244: 2242: 2241: 2236: 2206: 2204: 2203: 2198: 2183: 2181: 2180: 2175: 2163: 2161: 2160: 2155: 2126: 2125: 2108: 2100: 2084: 2083: 2067: 2065: 2064: 2059: 2047: 2045: 2044: 2039: 2027: 2025: 2024: 2019: 2002: 2001: 1985: 1983: 1982: 1977: 1965: 1963: 1962: 1957: 1945: 1943: 1942: 1937: 1911: 1910: 1894: 1892: 1891: 1886: 1862: 1860: 1859: 1854: 1837: 1836: 1824: 1803: 1801: 1800: 1795: 1783: 1781: 1780: 1775: 1763: 1761: 1760: 1755: 1743: 1741: 1740: 1735: 1723: 1721: 1720: 1715: 1694: 1692: 1691: 1686: 1674: 1672: 1671: 1666: 1644: 1642: 1641: 1636: 1624: 1622: 1621: 1616: 1614: 1598: 1596: 1595: 1590: 1575: 1573: 1572: 1567: 1555: 1553: 1552: 1547: 1535: 1533: 1532: 1527: 1500: 1498: 1497: 1492: 1487: 1467: 1443: 1441: 1440: 1435: 1423: 1421: 1420: 1415: 1398: 1384: 1372: 1370: 1369: 1364: 1356: 1317: 1315: 1314: 1309: 1301: 1275: 1250:Scott-continuous 1247: 1245: 1244: 1239: 1227: 1225: 1224: 1219: 1192: 1190: 1189: 1184: 1169: 1167: 1166: 1161: 1149: 1147: 1146: 1141: 1126: 1124: 1123: 1118: 1116: 1101: 1099: 1098: 1093: 1031: 1010: 1008: 1007: 1002: 991: 990: 969: 968: 946: 944: 943: 938: 924: 923: 893: 892: 864: 862: 861: 856: 845: 844: 817: 816: 797: 795: 794: 789: 777: 775: 774: 769: 755: 754: 727: 726: 700: 698: 697: 692: 690: 689: 684: 660: 659: 632: 631: 615: 613: 612: 607: 583: 581: 580: 575: 556: 554: 553: 548: 536: 534: 533: 528: 478: 476: 475: 470: 468: 467: 464: 451: 449: 448: 443: 441: 437: 433: 432: 409: 408: 375: 374: 371: 340: 338: 337: 332: 315: 314: 230: 228: 227: 222: 199: 197: 196: 191: 170:Scott-continuous 167: 165: 164: 159: 131: 129: 128: 123: 53: 51: 50: 47: 44: 2438: 2437: 2433: 2432: 2431: 2429: 2428: 2427: 2408: 2407: 2406: 2405: 2398: 2371: 2370: 2366: 2348: 2347: 2343: 2324: 2323: 2319: 2314: 2301: 2252: 2247: 2246: 2209: 2208: 2186: 2185: 2166: 2165: 2111: 2075: 2070: 2069: 2050: 2049: 2030: 2029: 1993: 1988: 1987: 1968: 1967: 1948: 1947: 1902: 1897: 1896: 1865: 1864: 1828: 1806: 1805: 1786: 1785: 1766: 1765: 1746: 1745: 1726: 1725: 1697: 1696: 1677: 1676: 1651: 1650: 1627: 1626: 1605: 1604: 1599:is in fact the 1581: 1580: 1579:The proof that 1558: 1557: 1538: 1537: 1503: 1502: 1446: 1445: 1426: 1425: 1375: 1374: 1320: 1319: 1254: 1253: 1230: 1229: 1195: 1194: 1175: 1174: 1152: 1151: 1129: 1128: 1107: 1106: 1022: 1021: 982: 954: 949: 948: 915: 878: 867: 866: 830: 808: 803: 802: 780: 779: 746: 718: 713: 712: 679: 645: 623: 618: 617: 586: 585: 566: 565: 539: 538: 519: 518: 512: 457: 456: 400: 399: 395: 391: 364: 363: 306: 250: 249: 210: 209: 204:, which is the 182: 181: 172:(and therefore 138: 137: 102: 101: 48: 45: 42: 41: 39: 24: 17: 12: 11: 5: 2436: 2434: 2426: 2425: 2420: 2410: 2409: 2404: 2403: 2396: 2364: 2341: 2316: 2315: 2313: 2310: 2309: 2308: 2300: 2297: 2285: 2282: 2279: 2276: 2273: 2270: 2265: 2262: 2259: 2255: 2234: 2231: 2228: 2225: 2222: 2219: 2216: 2196: 2193: 2173: 2153: 2150: 2147: 2144: 2141: 2138: 2135: 2132: 2129: 2124: 2121: 2118: 2114: 2106: 2099: 2096: 2093: 2090: 2087: 2082: 2078: 2057: 2037: 2017: 2014: 2011: 2008: 2005: 2000: 1996: 1975: 1955: 1935: 1932: 1929: 1926: 1923: 1920: 1917: 1914: 1909: 1905: 1884: 1881: 1878: 1875: 1872: 1852: 1849: 1846: 1843: 1840: 1835: 1831: 1827: 1823: 1819: 1816: 1813: 1793: 1773: 1753: 1733: 1713: 1710: 1707: 1704: 1684: 1664: 1661: 1658: 1634: 1613: 1588: 1565: 1545: 1525: 1522: 1519: 1516: 1513: 1510: 1490: 1486: 1482: 1479: 1476: 1473: 1470: 1466: 1462: 1459: 1456: 1453: 1433: 1413: 1410: 1407: 1404: 1401: 1397: 1393: 1390: 1387: 1383: 1373:. Also, since 1362: 1359: 1355: 1351: 1348: 1345: 1342: 1339: 1336: 1333: 1330: 1327: 1307: 1304: 1300: 1296: 1293: 1290: 1287: 1284: 1281: 1278: 1274: 1270: 1267: 1264: 1261: 1237: 1217: 1214: 1211: 1208: 1205: 1202: 1182: 1159: 1139: 1136: 1115: 1103: 1102: 1091: 1088: 1085: 1082: 1079: 1076: 1073: 1070: 1067: 1064: 1061: 1058: 1055: 1052: 1049: 1046: 1043: 1040: 1037: 1034: 1030: 1015: 1014: 1013: 1012: 1000: 997: 994: 989: 985: 981: 978: 975: 972: 967: 964: 961: 957: 936: 933: 930: 927: 922: 918: 914: 911: 908: 905: 902: 899: 896: 891: 888: 885: 881: 877: 874: 854: 851: 848: 843: 840: 837: 833: 829: 826: 823: 820: 815: 811: 799: 787: 767: 764: 761: 758: 753: 749: 745: 742: 739: 736: 733: 730: 725: 721: 702: 701: 688: 683: 678: 675: 672: 669: 666: 663: 658: 655: 652: 648: 644: 641: 638: 635: 630: 626: 605: 602: 599: 596: 593: 573: 546: 526: 511: 508: 453: 452: 440: 436: 431: 427: 424: 421: 418: 415: 412: 407: 403: 398: 394: 390: 387: 384: 381: 378: 342: 341: 330: 327: 324: 321: 318: 313: 309: 305: 302: 299: 296: 293: 290: 287: 284: 281: 278: 275: 272: 269: 266: 263: 260: 257: 232: 231: 220: 217: 189: 157: 154: 151: 148: 145: 121: 118: 115: 112: 109: 83:lattice theory 15: 13: 10: 9: 6: 4: 3: 2: 2435: 2424: 2421: 2419: 2416: 2415: 2413: 2399: 2393: 2389: 2385: 2381: 2377: 2376: 2368: 2365: 2360: 2356: 2352: 2345: 2342: 2336: 2332: 2328: 2321: 2318: 2311: 2307: 2303: 2302: 2298: 2296: 2283: 2280: 2277: 2263: 2260: 2257: 2253: 2232: 2229: 2226: 2220: 2214: 2207:we know that 2194: 2191: 2171: 2151: 2145: 2139: 2136: 2122: 2119: 2116: 2112: 2097: 2094: 2080: 2076: 2055: 2035: 2015: 2012: 1998: 1994: 1973: 1933: 1930: 1927: 1921: 1907: 1903: 1879: 1876: 1873: 1850: 1847: 1833: 1829: 1825: 1817: 1814: 1791: 1771: 1751: 1731: 1708: 1682: 1662: 1659: 1656: 1648: 1632: 1602: 1586: 1577: 1563: 1543: 1523: 1520: 1514: 1508: 1474: 1457: 1402: 1388: 1385: 1346: 1337: 1331: 1325: 1291: 1282: 1259: 1251: 1235: 1215: 1212: 1206: 1200: 1180: 1171: 1157: 1137: 1134: 1089: 1083: 1080: 1065: 1059: 1056: 1044: 1041: 1032: 1020: 1019: 1018: 987: 983: 979: 965: 962: 959: 955: 920: 916: 909: 906: 889: 886: 883: 879: 872: 841: 838: 835: 831: 827: 813: 809: 800: 765: 751: 747: 743: 737: 723: 719: 710: 709: 707: 704: 703: 686: 676: 673: 670: 656: 653: 650: 646: 642: 628: 624: 603: 597: 594: 591: 571: 563: 560: 559: 558: 544: 524: 515: 509: 507: 505: 501: 500:Alfred Tarski 497: 493: 489: 485: 480: 438: 434: 425: 422: 419: 405: 401: 396: 392: 385: 379: 362: 361: 360: 358: 354: 353:least element 350: 347: 328: 325: 311: 307: 303: 300: 297: 282: 276: 273: 261: 258: 248: 247: 246: 245: 241: 237: 218: 215: 207: 203: 187: 179: 175: 171: 155: 149: 146: 143: 135: 116: 113: 110: 99: 96: 95: 94: 92: 88: 84: 80: 76: 68: 64: 60: 56: 37: 33: 28: 22: 2418:Order theory 2374: 2367: 2358: 2354: 2344: 2334: 2330: 2320: 1600: 1578: 1424:and because 1172: 1104: 1016: 705: 561: 516: 513: 487: 481: 454: 356: 348: 344:obtained by 343: 239: 235: 233: 97: 86: 75:mathematical 72: 62: 54: 35: 31: 2339:, page 305. 2412:Categories 2397:0521383447 2337:: 285–309. 2312:References 1695:then also 1318:, that is 1228:. Because 537:exists in 2278:⊑ 2272:⊥ 2137:⊑ 2131:⊥ 2105:⟹ 2095:⊑ 2089:⊥ 2013:⊑ 2007:⊥ 1954:⊥ 1928:⊑ 1925:⊥ 1916:⊥ 1848:⊑ 1842:⊥ 1818:∈ 1812:∀ 1660:⊆ 1536:, making 1432:⊥ 1409:⊥ 1403:∪ 1084:… 1072:⊥ 1051:⊥ 1039:⊥ 996:⊥ 980:⊑ 974:⊥ 963:− 929:⊥ 907:⊑ 898:⊥ 887:− 850:⊥ 828:⊑ 822:⊥ 786:⊥ 760:⊥ 744:⊑ 741:⊥ 732:⊥ 677:∈ 665:⊥ 643:⊑ 637:⊥ 601:→ 482:Although 426:∈ 420:∣ 414:⊥ 346:iterating 329:⋯ 326:⊑ 320:⊥ 304:⊑ 301:⋯ 298:⊑ 289:⊥ 274:⊑ 268:⊥ 259:⊑ 256:⊥ 153:→ 117:⊑ 77:areas of 2361:: 43–57. 2299:See also 1647:supremum 514:Source: 206:supremum 178:function 174:monotone 100:Suppose 67:interval 351:on the 242:is the 180:. Then 73:In the 52:⁠ 40:⁠ 2394:  2304:Other 2109:  2101:  1946:since 778:since 706:Proof. 562:Lemma. 455:where 200:has a 85:, the 1804:that 1601:least 510:Proof 355:⊥ of 244:chain 168:be a 132:is a 79:order 2392:ISBN 2359:82:1 234:The 81:and 59:atan 38:) = 2384:doi 2335:5:2 1703:sup 1478:sup 1452:sup 1341:sup 1286:sup 1266:sup 1248:is 564:If 494:on 465:lfp 389:sup 372:lfp 238:of 2414:: 2390:. 2382:. 2380:24 2357:. 2353:. 2333:. 2329:. 1576:. 1252:, 176:) 49:10 2400:. 2386:: 2284:. 2281:k 2275:) 2269:( 2264:1 2261:+ 2258:i 2254:f 2233:, 2230:k 2227:= 2224:) 2221:k 2218:( 2215:f 2195:, 2192:f 2172:k 2152:. 2149:) 2146:k 2143:( 2140:f 2134:) 2128:( 2123:1 2120:+ 2117:i 2113:f 2098:k 2092:) 2086:( 2081:i 2077:f 2056:f 2036:f 2016:k 2010:) 2004:( 1999:i 1995:f 1974:L 1934:, 1931:k 1922:= 1919:) 1913:( 1908:0 1904:f 1883:) 1880:0 1877:= 1874:i 1871:( 1851:k 1845:) 1839:( 1834:i 1830:f 1826:: 1822:N 1815:i 1792:i 1772:f 1752:k 1732:L 1712:) 1709:D 1706:( 1683:L 1663:L 1657:D 1633:f 1612:M 1587:m 1564:f 1544:m 1524:m 1521:= 1518:) 1515:m 1512:( 1509:f 1489:) 1485:M 1481:( 1475:= 1472:) 1469:) 1465:M 1461:( 1458:f 1455:( 1412:} 1406:{ 1400:) 1396:M 1392:( 1389:f 1386:= 1382:M 1361:) 1358:) 1354:M 1350:( 1347:f 1344:( 1338:= 1335:) 1332:m 1329:( 1326:f 1306:) 1303:) 1299:M 1295:( 1292:f 1289:( 1283:= 1280:) 1277:) 1273:M 1269:( 1263:( 1260:f 1236:f 1216:m 1213:= 1210:) 1207:m 1204:( 1201:f 1181:m 1158:m 1138:. 1135:m 1114:M 1090:. 1087:} 1081:, 1078:) 1075:) 1069:( 1066:f 1063:( 1060:f 1057:, 1054:) 1048:( 1045:f 1042:, 1036:{ 1033:= 1029:M 999:) 993:( 988:n 984:f 977:) 971:( 966:1 960:n 956:f 935:) 932:) 926:( 921:n 917:f 913:( 910:f 904:) 901:) 895:( 890:1 884:n 880:f 876:( 873:f 853:) 847:( 842:1 839:+ 836:n 832:f 825:) 819:( 814:n 810:f 766:, 763:) 757:( 752:1 748:f 738:= 735:) 729:( 724:0 720:f 687:0 682:N 674:n 671:, 668:) 662:( 657:1 654:+ 651:n 647:f 640:) 634:( 629:n 625:f 604:L 598:L 595:: 592:f 572:L 545:L 525:f 488:f 439:) 435:} 430:N 423:n 417:) 411:( 406:n 402:f 397:{ 393:( 386:= 383:) 380:f 377:( 357:L 349:f 323:) 317:( 312:n 308:f 295:) 292:) 286:( 283:f 280:( 277:f 271:) 265:( 262:f 240:f 219:. 216:f 188:f 156:L 150:L 147:: 144:f 120:) 114:, 111:L 108:( 63:x 61:( 57:+ 55:x 46:/ 43:1 36:x 34:( 32:f 23:.

Index

Kleene's recursion theorem

atan
interval
mathematical
order
lattice theory
Stephen Cole Kleene
directed-complete partial order
Scott-continuous
monotone
function
least fixed point
supremum
chain
iterating
least element
Tarski's fixed point theorem
monotone functions
complete lattices
Alfred Tarski
monotone functions
Scott-continuous
supremum
fixed-point theorems
"A lattice-theoretical fixpoint theorem and its applications"
"Constructive versions of Tarski's fixed point theorems"
Mathematical Theory of Domains by V. Stoltenberg-Hansen
24
doi

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