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Fermat primality test

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are Fermat liars. For these numbers, repeated application of the Fermat primality test performs the same as a simple random search for factors. While Carmichael numbers are substantially rarer than prime numbers (Erdös' upper bound for the number of Carmichael numbers is lower than the
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As an exception, OpenPFGW uses only the Fermat test for probable prime testing. The program is typically used with multi-thousand digit inputs with a goal of maximum speed with very large inputs. Another well known program that relies only on the Fermat test is
1354: 2383: 652: 565: 1066: 771: 456: 1110: 969: 120: 368: 2387: 257: 208: 1895: 1223: 303: 1390: 1440: 1928: 1710: 1215: 1188: 1161: 976:) there are enough of them that Fermat's primality test is not often used in the above form. Instead, other more powerful extensions of the Fermat test, such as 1134: 1009: 925: 901: 1473:
In practice with most big number libraries such as GMP, the Fermat test is not noticeably faster than a Miller–Rabin test, and can be slower for many inputs.
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test for primality. Sometimes a Fermat test (along with some trial division by small primes) is performed first to improve performance.
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So 221 is composite and 38 was indeed a Fermat liar. Furthermore, 24 is a Fermat witness for the compositeness of 221.
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since version 3.0 uses a base-210 Fermat test after trial division and before running Miller–Rabin tests.
217: 2393: 2343: 2323: 1852: 1650: 813: 171: 1349:{\displaystyle (a\cdot a_{i})^{n-1}\equiv a^{n-1}\cdot a_{i}^{n-1}\equiv a^{n-1}\not \equiv 1{\pmod {n}}} 2044: 2019: 1580: 2403: 1775: 2398: 2290: 2272: 2247: 2209: 1953: 1672: 1481:
where it is only used for testing of self-generated large random values (an open source counterpart,
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is a composite number that is not a Carmichael number, then at least half of all
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is composite. Therefore, if the equality does hold for one or more values of
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and multiprecision multiplication, the running time of this algorithm is
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and see whether the congruence holds. If it does not hold for a value of
1601: 1546: 1467: 684:: a parameter that determines the number of times to test for primality 493: = 38. We check the above congruence and find that it holds: 263:
is odd, for the same reason. That is why one usually chooses a random
1593: 647:{\displaystyle a^{n-1}=24^{220}\equiv 81\not \equiv 1{\pmod {221}}.} 1720: 19:
For the test for determining whether a Fermat number is prime, see
1689:(Second ed.). MIT Press; McGraw-Hill. p. 889–890. 570:
Either 221 is prime, or 38 is a Fermat liar, so we take another
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is composite. This congruence is unlikely to hold for a random
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Verification of the Miller–Rabin Probabilistic Primality Test
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uses a similar process with base 2 for the Fermat test, but
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However, note that the above congruence holds trivially for
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indicate that algorithm is for numbers of special forms
560:{\displaystyle a^{n-1}=38^{220}\equiv 1{\pmod {221}}.} 1398: 1365: 1226: 1196: 1169: 1142: 1122: 1074: 1061:{\displaystyle a\in (\mathbb {Z} /n\mathbb {Z} )^{*}} 1020: 997: 933: 913: 889: 724: 583: 502: 409: 321: 273: 220: 174: 70: 2352: 2314: 2281: 2238: 2182: 2139: 2043: 2005: 1914: 1824: 1758: 1618:(1956). "On pseudoprimes and Carmichael numbers". 1434: 1384: 1348: 1209: 1182: 1155: 1128: 1104: 1060: 1003: 963: 919: 895: 765: 646: 559: 450: 362: 297: 251: 202: 114: 859:is the value we want to test for primality; see 804:respectively, hence testing them adds no value. 485: = 221 is prime. Randomly pick 1 < 766:{\displaystyle a^{n-1}\not \equiv 1{\pmod {n}}} 451:{\displaystyle a^{n-1}\not \equiv 1{\pmod {n}}} 1573:"There are Infinitely Many Carmichael Numbers" 1116:are Fermat witnesses. For proof of this, let 879:> 1. Even worse, there are infinitely many 796:-1 are not used as the equality holds for all 1889: 1736: 8: 1709:: CS1 maint: multiple names: authors list ( 1450:As mentioned above, most applications use a 1832:List of things named after Pierre de Fermat 1683:(2001). "Section 31.8: Primality testing". 1105:{\displaystyle \operatorname {gcd} (a,n)=1} 964:{\displaystyle \operatorname {gcd} (a,n)=1} 129:is prime, then we can pick random integers 115:{\displaystyle a^{p-1}\equiv 1{\pmod {p}}.} 1896: 1882: 1874: 1743: 1729: 1721: 363:{\displaystyle a^{n-1}\equiv 1{\pmod {n}}} 1654: 1536: 1397: 1376: 1364: 1330: 1312: 1293: 1288: 1269: 1250: 1240: 1225: 1201: 1195: 1174: 1168: 1147: 1141: 1121: 1073: 1052: 1044: 1043: 1035: 1031: 1030: 1019: 996: 932: 912: 888: 747: 729: 723: 665:The algorithm can be written as follows: 625: 607: 588: 582: 538: 526: 507: 501: 432: 414: 408: 344: 326: 320: 272: 233: 219: 184: 173: 93: 75: 69: 851:is the number of times we test a random 34:test to determine whether a number is a 1806:Fermat's theorem on sums of two squares 1494: 781:If composite is never returned: return 1837:Wiles's proof of Fermat's Last Theorem 1702: 1500: 1498: 481:Suppose we wish to determine whether 252:{\displaystyle a\equiv -1{\pmod {p}}} 210:, because the congruence relation is 7: 1801:Fermat's theorem (stationary points) 203:{\displaystyle a\equiv 1{\pmod {p}}} 1338: 755: 633: 546: 440: 352: 241: 192: 101: 14: 2105:Special number field sieve (SNFS) 2099:General number field sieve (GNFS) 1538:10.1090/S0025-5718-1980-0572872-7 676:: a value to test for primality, 1842:Fermat's Last Theorem in fiction 1816:Fermat's right triangle theorem 1786:Fermat polygonal number theorem 1331: 748: 626: 539: 433: 345: 234: 185: 94: 1342: 1332: 1247: 1227: 1093: 1081: 1049: 1027: 974:prime number function n/log(n) 952: 940: 759: 749: 637: 627: 550: 540: 444: 434: 356: 346: 245: 235: 214:. It also holds trivially for 212:compatible with exponentiation 196: 186: 105: 95: 1: 298:{\displaystyle 1<a<p-1} 125:If one wants to test whether 2063:Lenstra elliptic curve (ECM) 1385:{\displaystyle a\cdot a_{i}} 16:Probabilistic primality test 1518:"The pseudoprimes to 25·10" 1435:{\displaystyle i=1,2,...,s} 861:Miller–Rabin primality test 377:is composite is known as a 2465: 2370:Exponentiation by squaring 2053:Continued fraction (CFRAC) 1686:Introduction to Algorithms 1525:Mathematics of Computation 871:There are infinitely many 812:Using fast algorithms for 18: 2417: 469:for the compositeness of 1136:be a Fermat witness and 988:are more commonly used. 698:is composite, otherwise 2283:Greatest common divisor 1781:Fermat's little theorem 1514:Samuel S. Wagstaff, Jr. 1217:be Fermat liars. Then 47:Fermat's little theorem 2394:Modular exponentiation 1864:(popular science book) 1442:are Fermat witnesses. 1436: 1386: 1350: 1211: 1184: 1157: 1130: 1106: 1062: 1005: 965: 921: 897: 814:modular exponentiation 767: 715:randomly in the range 648: 561: 452: 364: 299: 253: 204: 116: 2121:Shanks's square forms 2045:Integer factorization 2020:Sieve of Eratosthenes 1861:Fermat's Last Theorem 1766:Fermat's Last Theorem 1581:Annals of Mathematics 1437: 1387: 1351: 1212: 1210:{\displaystyle a_{s}} 1185: 1183:{\displaystyle a_{2}} 1158: 1156:{\displaystyle a_{1}} 1131: 1107: 1063: 1006: 966: 922: 898: 768: 649: 562: 453: 365: 300: 254: 205: 117: 28:Fermat primality test 2399:Montgomery reduction 2273:Function field sieve 2248:Baby-step giant-step 2094:Quadratic sieve (QS) 1673:Charles E. Leiserson 1620:Publ. Math. Debrecen 1396: 1363: 1224: 1194: 1167: 1140: 1120: 1072: 1018: 995: 931: 911: 887: 883:. These are numbers 722: 581: 500: 407: 319: 271: 218: 172: 68: 57:is not divisible by 2409:Trachtenberg system 2375:Integer square root 2316:Modular square root 2035:Wheel factorization 1987:Quadratic Frobenius 1967:Lucas–Lehmer–Riesel 1853:Fermat's Last Tango 1304: 875:to any given basis 873:Fermat pseudoprimes 157:, then we say that 2449:Modular arithmetic 2301:Extended Euclidean 2240:Discrete logarithm 2169:Schönhage–Strassen 2025:Sieve of Pritchard 1791:Fermat pseudoprime 1776:Fermat's principle 1531:(151): 1003–1026. 1432: 1382: 1346: 1284: 1207: 1180: 1153: 1126: 1102: 1058: 1001: 961: 917: 893: 881:Carmichael numbers 763: 644: 557: 448: 387:Fermat pseudoprime 360: 295: 249: 200: 112: 2431: 2430: 2030:Sieve of Sundaram 1871: 1870: 1645:Joe Hurd (2003), 1565:Granville, Andrew 1510:John L. Selfridge 1483:GNU Privacy Guard 1129:{\displaystyle a} 1004:{\displaystyle n} 920:{\displaystyle a} 896:{\displaystyle n} 396:If we do pick an 133:not divisible by 2456: 2380:Integer relation 2353:Other algorithms 2258:Pollard kangaroo 2149:Ancient Egyptian 2007:Prime-generating 1992:Solovay–Strassen 1905:Number-theoretic 1898: 1891: 1884: 1875: 1752:Pierre de Fermat 1745: 1738: 1731: 1722: 1714: 1708: 1700: 1677:Ronald L. Rivest 1669:Thomas H. Cormen 1660: 1659: 1658: 1642: 1636: 1635: 1612: 1606: 1605: 1577: 1557: 1551: 1550: 1540: 1522: 1502: 1441: 1439: 1438: 1433: 1391: 1389: 1388: 1383: 1381: 1380: 1355: 1353: 1352: 1347: 1345: 1323: 1322: 1303: 1292: 1280: 1279: 1261: 1260: 1245: 1244: 1216: 1214: 1213: 1208: 1206: 1205: 1189: 1187: 1186: 1181: 1179: 1178: 1162: 1160: 1159: 1154: 1152: 1151: 1135: 1133: 1132: 1127: 1111: 1109: 1108: 1103: 1067: 1065: 1064: 1059: 1057: 1056: 1047: 1039: 1034: 1010: 1008: 1007: 1002: 986:Solovay–Strassen 970: 968: 967: 962: 926: 924: 923: 918: 902: 900: 899: 894: 846: 772: 770: 769: 764: 762: 740: 739: 653: 651: 650: 645: 640: 612: 611: 599: 598: 566: 564: 563: 558: 553: 531: 530: 518: 517: 457: 455: 454: 449: 447: 425: 424: 369: 367: 366: 361: 359: 337: 336: 304: 302: 301: 296: 267:in the interval 258: 256: 255: 250: 248: 209: 207: 206: 201: 199: 121: 119: 118: 113: 108: 86: 85: 2464: 2463: 2459: 2458: 2457: 2455: 2454: 2453: 2444:Primality tests 2434: 2433: 2432: 2427: 2413: 2348: 2310: 2277: 2234: 2178: 2135: 2039: 2001: 1974:Proth's theorem 1916:Primality tests 1910: 1902: 1872: 1867: 1820: 1811:Fermat's spiral 1754: 1749: 1718: 1701: 1697: 1667: 1664: 1663: 1656:10.1.1.105.3196 1644: 1643: 1639: 1614: 1613: 1609: 1594:10.2307/2118576 1575: 1569:Pomerance, Carl 1559: 1558: 1554: 1520: 1504: 1503: 1496: 1491: 1448: 1394: 1393: 1372: 1361: 1360: 1308: 1265: 1246: 1236: 1222: 1221: 1197: 1192: 1191: 1170: 1165: 1164: 1143: 1138: 1137: 1118: 1117: 1070: 1069: 1048: 1016: 1015: 993: 992: 991:In general, if 929: 928: 909: 908: 885: 884: 869: 817: 810: 725: 720: 719: 663: 603: 584: 579: 578: 522: 503: 498: 497: 479: 410: 405: 404: 381:. In this case 322: 317: 316: 269: 268: 216: 215: 170: 169: 71: 66: 65: 49:states that if 44: 24: 17: 12: 11: 5: 2462: 2460: 2452: 2451: 2446: 2436: 2435: 2429: 2428: 2426: 2425: 2418: 2415: 2414: 2412: 2411: 2406: 2401: 2396: 2391: 2377: 2372: 2367: 2362: 2356: 2354: 2350: 2349: 2347: 2346: 2341: 2336: 2334:Tonelli–Shanks 2331: 2326: 2320: 2318: 2312: 2311: 2309: 2308: 2303: 2298: 2293: 2287: 2285: 2279: 2278: 2276: 2275: 2270: 2268:Index calculus 2265: 2263:Pohlig–Hellman 2260: 2255: 2250: 2244: 2242: 2236: 2235: 2233: 2232: 2227: 2222: 2217: 2215:Newton-Raphson 2212: 2207: 2202: 2197: 2191: 2189: 2180: 2179: 2177: 2176: 2171: 2166: 2161: 2156: 2151: 2145: 2143: 2141:Multiplication 2137: 2136: 2134: 2133: 2128: 2126:Trial division 2123: 2118: 2113: 2111:Rational sieve 2108: 2101: 2096: 2091: 2083: 2075: 2070: 2065: 2060: 2055: 2049: 2047: 2041: 2040: 2038: 2037: 2032: 2027: 2022: 2017: 2015:Sieve of Atkin 2011: 2009: 2003: 2002: 2000: 1999: 1994: 1989: 1984: 1977: 1970: 1963: 1956: 1951: 1946: 1941: 1939:Elliptic curve 1936: 1931: 1926: 1920: 1918: 1912: 1911: 1903: 1901: 1900: 1893: 1886: 1878: 1869: 1868: 1866: 1865: 1857: 1856:(2000 musical) 1849: 1844: 1839: 1834: 1828: 1826: 1822: 1821: 1819: 1818: 1813: 1808: 1803: 1798: 1793: 1788: 1783: 1778: 1773: 1768: 1762: 1760: 1756: 1755: 1750: 1748: 1747: 1740: 1733: 1725: 1716: 1715: 1695: 1681:Clifford Stein 1662: 1661: 1637: 1607: 1588:(3): 703–722. 1552: 1506:Carl Pomerance 1493: 1492: 1490: 1487: 1447: 1444: 1431: 1428: 1425: 1422: 1419: 1416: 1413: 1410: 1407: 1404: 1401: 1379: 1375: 1371: 1368: 1357: 1356: 1344: 1341: 1337: 1334: 1329: 1326: 1321: 1318: 1315: 1311: 1307: 1302: 1299: 1296: 1291: 1287: 1283: 1278: 1275: 1272: 1268: 1264: 1259: 1256: 1253: 1249: 1243: 1239: 1235: 1232: 1229: 1204: 1200: 1177: 1173: 1150: 1146: 1125: 1114: 1113: 1101: 1098: 1095: 1092: 1089: 1086: 1083: 1080: 1077: 1055: 1051: 1046: 1042: 1038: 1033: 1029: 1026: 1023: 1000: 960: 957: 954: 951: 948: 945: 942: 939: 936: 916: 906: 892: 868: 865: 809: 806: 786: 785: 783:probably prime 779: 778: 777: 773:, then return 761: 758: 754: 751: 746: 743: 738: 735: 732: 728: 716: 702: 700:probably prime 685: 662: 659: 655: 654: 643: 639: 636: 632: 629: 624: 621: 618: 615: 610: 606: 602: 597: 594: 591: 587: 568: 567: 556: 552: 549: 545: 542: 537: 534: 529: 525: 521: 516: 513: 510: 506: 489:< 220, say 478: 475: 467:Fermat witness 465:is known as a 459: 458: 446: 443: 439: 436: 431: 428: 423: 420: 417: 413: 371: 370: 358: 355: 351: 348: 343: 340: 335: 332: 329: 325: 294: 291: 288: 285: 282: 279: 276: 247: 244: 240: 237: 232: 229: 226: 223: 198: 195: 191: 188: 183: 180: 177: 163:probably prime 123: 122: 111: 107: 104: 100: 97: 92: 89: 84: 81: 78: 74: 43: 40: 36:probable prime 15: 13: 10: 9: 6: 4: 3: 2: 2461: 2450: 2447: 2445: 2442: 2441: 2439: 2423: 2420: 2419: 2416: 2410: 2407: 2405: 2402: 2400: 2397: 2395: 2392: 2389: 2385: 2381: 2378: 2376: 2373: 2371: 2368: 2366: 2363: 2361: 2358: 2357: 2355: 2351: 2345: 2342: 2340: 2337: 2335: 2332: 2330: 2329:Pocklington's 2327: 2325: 2322: 2321: 2319: 2317: 2313: 2307: 2304: 2302: 2299: 2297: 2294: 2292: 2289: 2288: 2286: 2284: 2280: 2274: 2271: 2269: 2266: 2264: 2261: 2259: 2256: 2254: 2251: 2249: 2246: 2245: 2243: 2241: 2237: 2231: 2228: 2226: 2223: 2221: 2218: 2216: 2213: 2211: 2208: 2206: 2203: 2201: 2198: 2196: 2193: 2192: 2190: 2188: 2185: 2181: 2175: 2172: 2170: 2167: 2165: 2162: 2160: 2157: 2155: 2152: 2150: 2147: 2146: 2144: 2142: 2138: 2132: 2129: 2127: 2124: 2122: 2119: 2117: 2114: 2112: 2109: 2107: 2106: 2102: 2100: 2097: 2095: 2092: 2090: 2088: 2084: 2082: 2080: 2076: 2074: 2073:Pollard's rho 2071: 2069: 2066: 2064: 2061: 2059: 2056: 2054: 2051: 2050: 2048: 2046: 2042: 2036: 2033: 2031: 2028: 2026: 2023: 2021: 2018: 2016: 2013: 2012: 2010: 2008: 2004: 1998: 1995: 1993: 1990: 1988: 1985: 1983: 1982: 1978: 1976: 1975: 1971: 1969: 1968: 1964: 1962: 1961: 1957: 1955: 1952: 1950: 1947: 1945: 1942: 1940: 1937: 1935: 1932: 1930: 1927: 1925: 1922: 1921: 1919: 1917: 1913: 1909: 1906: 1899: 1894: 1892: 1887: 1885: 1880: 1879: 1876: 1863: 1862: 1858: 1855: 1854: 1850: 1848: 1845: 1843: 1840: 1838: 1835: 1833: 1830: 1829: 1827: 1823: 1817: 1814: 1812: 1809: 1807: 1804: 1802: 1799: 1797: 1794: 1792: 1789: 1787: 1784: 1782: 1779: 1777: 1774: 1772: 1771:Fermat number 1769: 1767: 1764: 1763: 1761: 1757: 1753: 1746: 1741: 1739: 1734: 1732: 1727: 1726: 1723: 1719: 1712: 1706: 1698: 1696:0-262-03293-7 1692: 1688: 1687: 1682: 1678: 1674: 1670: 1666: 1665: 1657: 1652: 1649:, p. 2, 1648: 1641: 1638: 1633: 1629: 1625: 1621: 1617: 1611: 1608: 1603: 1599: 1595: 1591: 1587: 1583: 1582: 1574: 1570: 1566: 1562: 1561:Alford, W. R. 1556: 1553: 1548: 1544: 1539: 1534: 1530: 1526: 1519: 1516:(July 1980). 1515: 1511: 1507: 1501: 1499: 1495: 1488: 1486: 1484: 1480: 1474: 1471: 1469: 1465: 1461: 1457: 1453: 1445: 1443: 1429: 1426: 1423: 1420: 1417: 1414: 1411: 1408: 1405: 1402: 1399: 1377: 1373: 1369: 1366: 1339: 1335: 1327: 1324: 1319: 1316: 1313: 1309: 1305: 1300: 1297: 1294: 1289: 1285: 1281: 1276: 1273: 1270: 1266: 1262: 1257: 1254: 1251: 1241: 1237: 1233: 1230: 1220: 1219: 1218: 1202: 1198: 1175: 1171: 1148: 1144: 1123: 1099: 1096: 1090: 1087: 1084: 1078: 1075: 1053: 1040: 1036: 1024: 1021: 1014: 1013: 1012: 998: 989: 987: 983: 979: 975: 958: 955: 949: 946: 943: 937: 934: 914: 904: 890: 882: 878: 874: 866: 864: 863:for details. 862: 858: 854: 850: 844: 840: 836: 832: 828: 824: 820: 815: 807: 805: 803: 799: 795: 792:values 1 and 791: 784: 780: 776: 756: 752: 744: 741: 736: 733: 730: 726: 717: 714: 710: 709: 707: 703: 701: 697: 693: 689: 686: 683: 679: 675: 671: 668: 667: 666: 660: 658: 641: 634: 630: 622: 619: 616: 613: 608: 604: 600: 595: 592: 589: 585: 577: 576: 575: 573: 554: 547: 543: 535: 532: 527: 523: 519: 514: 511: 508: 504: 496: 495: 494: 492: 488: 484: 476: 474: 472: 468: 464: 441: 437: 429: 426: 421: 418: 415: 411: 403: 402: 401: 399: 394: 392: 388: 384: 380: 376: 353: 349: 341: 338: 333: 330: 327: 323: 315: 314: 313: 311: 306: 292: 289: 286: 283: 280: 277: 274: 266: 262: 242: 238: 230: 227: 224: 221: 213: 193: 189: 181: 178: 175: 166: 164: 160: 156: 152: 148: 144: 140: 136: 132: 128: 109: 102: 98: 90: 87: 82: 79: 76: 72: 64: 63: 62: 60: 56: 53:is prime and 52: 48: 41: 39: 37: 33: 32:probabilistic 29: 22: 2421: 2103: 2086: 2078: 1997:Miller–Rabin 1979: 1972: 1965: 1960:Lucas–Lehmer 1958: 1948: 1859: 1851: 1847:Fermat Prize 1796:Fermat point 1717: 1685: 1646: 1640: 1623: 1619: 1610: 1585: 1579: 1555: 1528: 1524: 1475: 1472: 1452:Miller–Rabin 1449: 1446:Applications 1358: 1115: 990: 982:Miller–Rabin 876: 870: 856: 852: 848: 842: 838: 830: 826: 822: 811: 801: 800:and all odd 797: 793: 789: 787: 782: 774: 712: 705: 699: 695: 691: 687: 681: 677: 673: 669: 664: 656: 571: 569: 490: 486: 482: 480: 470: 466: 462: 460: 397: 395: 390: 382: 378: 374: 372: 309: 307: 264: 260: 167: 158: 154: 150: 146: 142: 138: 134: 130: 126: 124: 58: 54: 50: 45: 27: 25: 21:PĂ©pin's test 2253:Pollard rho 2210:Goldschmidt 1944:Pocklington 1934:Baillie–PSW 1626:: 201–206. 1456:Baillie–PSW 1359:and so all 978:Baillie–PSW 400:such that 379:Fermat liar 312:such that 2438:Categories 2365:Cornacchia 2360:Chakravala 1908:algorithms 1616:Paul ErdƑs 1489:References 1470:does not. 907:values of 903:for which 808:Complexity 574:, say 24: 385:is called 2339:Berlekamp 2296:Euclidean 2184:Euclidean 2164:Toom–Cook 2159:Karatsuba 1705:cite book 1651:CiteSeerX 1464:Libgcrypt 1370:⋅ 1317:− 1306:≡ 1298:− 1282:⋅ 1274:− 1263:≡ 1255:− 1234:⋅ 1079:⁡ 1054:∗ 1025:∈ 938:⁡ 841: log 775:composite 734:− 692:composite 661:Algorithm 614:≡ 593:− 533:≡ 512:− 419:− 339:≡ 331:− 290:− 228:− 225:≡ 179:≡ 88:≡ 80:− 2306:Lehmer's 2200:Chunking 2187:division 2116:Fermat's 1571:(1994). 1325:≢ 847:, where 829:log log 742:≢ 620:≢ 427:≢ 389:to base 2422:Italics 2344:Kunerth 2324:Cipolla 2205:Fourier 2174:FĂŒrer's 2068:Euler's 2058:Dixon's 1981:PĂ©pin's 1825:Related 1632:0079031 1602:2118576 1547:2006210 1468:OpenSSL 1190:, ..., 708:times: 704:Repeat 680:>3; 477:Example 141:, then 61:, then 42:Concept 2404:Schoof 2291:Binary 2195:Binary 2131:Shor's 1949:Fermat 1693:  1653:  1630:  1600:  1545:  1068:(i.e. 984:, and 855:, and 688:Output 670:Inputs 2225:Short 1954:Lucas 1598:JSTOR 1576:(PDF) 1543:JSTOR 1521:(PDF) 927:with 711:Pick 461:then 373:when 30:is a 2220:Long 2154:Long 1759:Work 1711:link 1691:ISBN 1392:for 867:Flaw 833:) = 788:The 308:Any 284:< 278:< 26:The 2384:LLL 2230:SRT 2089:+ 1 2081:− 1 1929:APR 1924:AKS 1590:doi 1586:140 1533:doi 1479:PGP 1460:GMP 1454:or 1336:mod 1076:gcd 935:gcd 905:all 825:log 753:mod 718:If 694:if 635:221 631:mod 609:220 548:221 544:mod 528:220 438:mod 350:mod 259:if 239:mod 190:mod 161:is 149:if 99:mod 2440:: 2388:KZ 2386:; 1707:}} 1703:{{ 1679:, 1675:, 1671:, 1628:MR 1622:. 1596:. 1584:. 1578:. 1567:; 1563:; 1541:. 1529:35 1527:. 1523:. 1512:; 1508:; 1497:^ 1163:, 980:, 690:: 672:: 617:81 605:24 524:38 473:. 393:. 305:. 165:. 38:. 2390:) 2382:( 2087:p 2079:p 1897:e 1890:t 1883:v 1744:e 1737:t 1730:v 1713:) 1699:. 1634:. 1624:4 1604:. 1592:: 1549:. 1535:: 1430:s 1427:, 1424:. 1421:. 1418:. 1415:, 1412:2 1409:, 1406:1 1403:= 1400:i 1378:i 1374:a 1367:a 1343:) 1340:n 1333:( 1328:1 1320:1 1314:n 1310:a 1301:1 1295:n 1290:i 1286:a 1277:1 1271:n 1267:a 1258:1 1252:n 1248:) 1242:i 1238:a 1231:a 1228:( 1203:s 1199:a 1176:2 1172:a 1149:1 1145:a 1124:a 1112:) 1100:1 1097:= 1094:) 1091:n 1088:, 1085:a 1082:( 1050:) 1045:Z 1041:n 1037:/ 1032:Z 1028:( 1022:a 999:n 959:1 956:= 953:) 950:n 947:, 944:a 941:( 915:a 891:n 877:a 857:n 853:a 849:k 845:) 843:n 839:k 837:( 835:Õ 831:n 827:n 823:k 821:( 819:O 802:n 798:n 794:n 790:a 760:) 757:n 750:( 745:1 737:1 731:n 727:a 713:a 706:k 696:n 682:k 678:n 674:n 642:. 638:) 628:( 623:1 601:= 596:1 590:n 586:a 572:a 555:. 551:) 541:( 536:1 520:= 515:1 509:n 505:a 491:a 487:a 483:n 471:n 463:a 445:) 442:n 435:( 430:1 422:1 416:n 412:a 398:a 391:a 383:n 375:n 357:) 354:n 347:( 342:1 334:1 328:n 324:a 310:a 293:1 287:p 281:a 275:1 265:a 261:p 246:) 243:p 236:( 231:1 222:a 197:) 194:p 187:( 182:1 176:a 159:p 155:a 151:p 147:a 143:p 139:a 135:p 131:a 127:p 110:. 106:) 103:p 96:( 91:1 83:1 77:p 73:a 59:p 55:a 51:p 23:.

Index

PĂ©pin's test
probabilistic
probable prime
Fermat's little theorem
probably prime
compatible with exponentiation
Fermat pseudoprime
modular exponentiation
O
Õ
Miller–Rabin primality test
Fermat pseudoprimes
Carmichael numbers
prime number function n/log(n)
Baillie–PSW
Miller–Rabin
Solovay–Strassen
Miller–Rabin
Baillie–PSW
GMP
Libgcrypt
OpenSSL
PGP
GNU Privacy Guard


Carl Pomerance
John L. Selfridge
Samuel S. Wagstaff, Jr.
"The pseudoprimes to 25·10"

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