Knowledge

Talk:Recursive language

Source 📝

2327:
the sentence about total Turing machines, since "algorithm" is very common usage for this concept in theoretical computer science. I do realize that this well-intended addition could also cause some confusion similar to what seems to have happened around the use of "recursive" here, but I did it for a good (at least in my opinion) reason. There is a debate about the term "algorithm" going on right now in the Talk page for another article in Knowledge, and I intend to try to help resolve the debate and (more importantly) to improve that article. To do that, I needed this article to mention "algorithm" as it is commonly used in teaching theoretical computer science.
1976:. Notice that even NP-complete decision problems, such as 3SAT, are languages that can be accepted by some LBA. The little we know about separation of complexity classes makes it even more difficult to find a witness. For example, it is conjectured, but we cannot prove, that EXPTIME-complete languages are not context-sensitive. In order to have a chance of proving that a language is not in CSL, we have to resort to decision problems that are much more difficult. Another example of a decidable set, which is provably not context-sensitive, is the set of first-order formulas in 2258:. Obviously the article is written in a dense style but I think that's okay as long as the introduction clarifies the context. I believe that improving readability of such articles is much more work (though desirable) than having discussions like this one. Currently, I have no suggestion how to slightly modify the introduction without introducing negative statements ("Recursive languages are unrelated to ..."). What is your expectation of the first sentences, now that you probably know a bit more about the subject? Would it help if the article on 253: 243: 222: 452: 2310:"Formal language" is defined in parentheses in the very first sentence of the article. In computer science terms: It's an arbitrary set of strings. Nothing more. No meaning attached whatsoever. This is a perfectly standard term in computer science, in mathematical logic and in linguistics, and anyone wo doesn't believe what he or she reads (I can understand why one wouldn't on first hearing that definition) can simply follow the link to 780: 606: 1049: 1024: 585: 2135:. When I read an article about "Recursive languages" I expect to be able to gain some understanding about the subject to know if this is true or not. This article is not sufficient for a knowledgeable reader such as me to gain any insight into the issue at all. If this article does *not* have any application to programming languages, it should make that clear. If it *does*, it should also make that clear. Thanks! 511: 703: 682: 191: 1571:
being a shorthand for ww. For example, we have (abba)²= abbaabba, ((abcab)²)²= abbaabbaabbaabba, and so on. Thus, there are regular expressions that can be described very succinctly using repeated squaring. We can transform a regular expression with squaring into an ordinary regular expression, but the length of the output can be exponential in the input length. Now consider the set
501: 480: 2109:, this connection is so remote that you had better think of them as unconnected. I don't think we have an article on SQL recursive queries, and I don't know if we should have one. But it's clear that recursive languages in the mathematics / pure computer science sense are a much more important topic and that this article should not be hijacked for the SQL topic. 354: 327: 364: 1681: 1563: 1302: 2235:
Thank you for your thoughtful reply. I suppose you have restated my point: I read the article and I could not make heads nor tails of it. My options are to a) assume that I am an idiot or b) assume that the article is opaque enough that a normally educated and aware reader cannot contextualize it. I
2080:
a topic of theory and not a classification of programming languages (and could therefore be perceived less important for programmers). However, to help reduce the complexity of the article, you can try to explain what makes you think that SQL is a recursive language and what you would expect to read
2326:
I agree that the treatment of formal language in the first paragraph is OK. Alas, computer science is rife with terms that have different meanings in different contexts. Along with "recursive", "algorithm" is another one. I took the liberty of slightly modifying this paragraph to add "algorithm" to
1570:
If we are looking for a language that is decidable but provably not context-sensitive, we need to look for a more difficult language. Assume now we extend the syntax of the usual regular expressions with the operations union, concatenation and Kleene star by adding the squaring operator ², with w²
2026:
This is too ambiguous. Obviously this set can not be enumerated, some of its members are actually infinite. I believe what the author intended was something along the lines of "the set of all Turing machines that accept recursive languages is not recursively enumerable", or "the set of all Turing
801: 1999:
For anyone keeping this article on their watchlist: there is currently an attempt at merging a number of articles on (non-)recursive/(un)decidable/(un)computable sets/languages/decision problems into a single, thorough article. The experiment currently sits at
1576: 153: 2056:
is a recursive language, and it is a language that virtually every programmer uses. These programmers should be able to read this article and understand the important aspects of recursive languages and how they are distinguished from
1739:. Then one can run a LBA whose input tape is the output tape of the previous Turing machine for deciding whether there is a word that is not described by the regular expression. Observe that the latter LBA requires space O(m), where 1458: 1232: 2190:
to be a programming language with Spanish keywords, and I haven't found a link from any programming language article to this one that could make you assume a relation. A recursively defined programming language uses
2219:
recursive (not: recursively defined). The article should not be hijacked/bloated with all kinds of disclaimers what the article is not about (in particular it's not about natural languages, recursive jokes, ...).
2051:
The concept of "recursive language" is an important one for all programmers and they need to be able to understand it. The article as it currently reads sheds little or no light on this issue. For example
1441:
Meyer, A.R., Stockmeyer, L.J.: The equivalence problem for regular expressions with squaring requires exponential space. In: Symposium on Switching and Automata Theory (SWAT 1972), pp. 125–129. IEEE (1972)
2330:
And by the way, I did note that the way I cited Prof. Sipser's textbook is not the way the moderators want us to do it, but I have not learned how to create proper citations yet. FWIW, it is on my to do
1421: 1453:
There are even notoriously difficult decision problems, whose associated language is context-sensitive. One such example is the inequivalence problem of regular expressions. More precisely, the set
1327:
implies the existence of recursive, but non-context-sensitive languages; I think this should be mentioned in the article. Apparently, a concrete language can't be given in a form as simple as, say,
1116: 825: 147: 1190: 309: 1208:
In order to illustrate the place of recursive languages in the (extended) Chomsky hierarchy, could somebody please give an example for a recursive language that isn't context-sensitive? -
965: 1712:
is decidable. Namely, a Turing machine with output tape can transform a regular expression with squaring of length 'n' into an equivalent ordinary regular expression of length at most
2023:
I just reverted an anonymous edit that added the following sentence: "Note: The set of all recursive languages can not be enumerated effectively. The proof is by diagonalization."
1676:{\displaystyle S_{2}=\{\,r\mid r{\mbox{ is a regular expression with squaring over the alphabet }}\{a,b\}{\mbox{ and }}r{\mbox{ does not describe all words in }}\{a,b\}^{*}\,\}} 882: 820: 1848: 1770: 2435: 1945: 753: 743: 2284:
I agree. There is a perfectly servicable introductory paragraph. It says: class of formal languages. What the heck is a formal language? That makes absolutely no sense.
1906: 1879: 1797: 1737: 1710: 385:
on Knowledge. If you would like to support the project, please visit the project page, where you can get more details on how you can help, and where you can join the
1974: 1558:{\displaystyle S_{1}=\{\,r\mid r{\mbox{ is a regular expression over the alphabet }}\{a,b\}{\mbox{ and }}r{\mbox{ does not describe all words in }}\{a,b\}^{*}\,\}} 1297:{\displaystyle \{\,r\mid r{\mbox{ is a regular expression with negation over the alphabet }}\{a,b\}{\mbox{ and the language described by }}r{\mbox{ is empty}}\,\}} 2440: 2430: 2405: 2165:” and so on), and its application to programming languages is very remote. (Specifically, a “recursive language” is not a programming language that supports 567: 557: 2380: 719: 422: 412: 1423:. Your regular expression example is closest to that form; do you have a reference for it (which should also establish that the language is recursive)? - 2420: 2370: 927: 664: 654: 299: 79: 44: 2211:
is about and then end up here, you might read the article with false expectations. But doesn't the first sentence clarify that the term is derived from
2410: 2400: 2365: 2375: 168: 2415: 1055: 1029: 135: 901: 1449:
Markus Holzer and Martin Kutrib: "The Complexity of Regular(-Like) Expressions", in: Y. Gao et al. (Eds.): DLT 2010, LNCS 6224, pp. 16–30, 2010.
1437:
I looked again into this, and found another language, that is a bit easier to describe. In what follows, I refer to the original research paper
2390: 766: 710: 687: 533: 275: 2236:
went with b) and all I am suggesting is that you review this article for slight modification with a lay reader in mind. Thanks for your time.
2030:
Anyway, such claims do not belong into the "closure properties" section, they should be stated more formally, and cite a suitable reference.
990: 387: 85: 1224: 630: 2061:. This article might be too mathematical. I am not qualified to judge that aspect of it, but I suspect that this article is just wrong.-- 2385: 873: 129: 2395: 854: 524: 485: 266: 227: 125: 377: 332: 2425: 946: 613: 590: 99: 30: 1330: 175: 104: 20: 2123:
I am a programmer not a theorist. My understanding is that many languages were purposely designed to be recursive, such as
74: 2166: 1853:
On the other hand, using techniques from computational complexity theory, one can prove that there is a constant 'c: -->
911: 792: 202: 1196:. So while it is true that it's recursive, this isn't an example that's particularly unique to recursive languages. – 2124: 921: 835: 459: 337: 65: 2208: 2174: 1428: 1213: 956: 718:
related articles on Knowledge. If you would like to participate, please visit the project page, where you can join
141: 2001: 1122: 983: 1227: 190: 2267: 2225: 2086: 1911:
Most languages that can be given in a simple form as you mentioned can be computed in nondeterministic time
1324: 109: 2170: 2338: 626: 1104: 2263: 2221: 2162: 2082: 1977: 1424: 1209: 892: 208: 252: 2318: 2315: 2192: 2113: 2110: 1060: 1034: 2058: 161: 55: 1802: 629:
on Knowledge. If you would like to participate, please visit the project page, where you can join
532:
on Knowledge. If you would like to participate, please visit the project page, where you can join
274:
on Knowledge. If you would like to participate, please visit the project page, where you can join
2009: 516: 258: 70: 24: 1742: 242: 221: 1567:
can be decided by a LBA, and is therefore context-sensitive (cf. Theorem 15 in Holzer/Kutrib).
2334: 811: 369: 51: 1914: 2289: 2241: 2200: 2187: 2158: 2140: 2066: 1985: 1309: 1193: 863: 715: 2311: 2154: 2037: 1884: 1857: 1775: 1715: 1688: 1950: 1881:
cannot be computed by any nondeterministic Turing machine whose space bound is less than
1197: 937: 779: 802:
Requested articles/Applied arts and sciences/Computer science, computing, and Internet
451: 2359: 2259: 2212: 2005: 2186:
I wonder why you actually thought the terms were related. You wouldn't expect the
2076:
I don't think the article is wrong in general. The concept of recursive languages
1223:
You can take any language that provably requires more than linear space, see here
1099:
I think that what's missing from this page is an example of a recursive language.
2285: 2237: 2136: 2062: 1981: 1305: 529: 271: 1048: 1023: 605: 584: 510: 2254:
I know the feeling too well that some articles tend to make you choose option
2033: 506: 382: 359: 248: 2342: 2321: 2293: 2271: 2245: 2229: 2204: 2196: 2178: 2144: 2128: 2116: 2090: 2070: 2041: 2013: 1989: 1432: 1313: 1217: 1200: 1107: 844: 622: 702: 681: 618: 1226:. For example, any EXPSPACE-complete language will do the job, see here 2169:.) Do you have a suggestion how the article could make this clearer? — 381:, a collaborative effort to improve the coverage of content related to 500: 479: 353: 326: 1229:. An example that is easier to describe is the following language: 2132: 2053: 1304:. This language is not in CSL (it is not even in ELEMENTARY). 920:
Find pictures for the biographies of computer scientists (see
184: 15: 2203:
can be recursively defined ). Of course, if you stumble upon
2153:
The term “recursive language” refers to a specific class of
450: 2027:
machines that are deciders is not recursively enumerable".
2101:. While there is ultimately some connection to the word 1610:
is a regular expression with squaring over the alphabet
1416:{\displaystyle \{a^{(2^{n})}b^{n!}c^{(n^{2})}|n\geq 1\}} 1253:
is a regular expression with negation over the alphabet
1640: 1630: 1608: 1522: 1512: 1490: 1283: 1273: 1251: 160: 1953: 1917: 1887: 1860: 1805: 1799:
is recursive, and can be decided using space at most
1778: 1745: 1718: 1691: 1579: 1461: 1333: 1235: 1125: 714:, a collaborative effort to improve the coverage of 617:, a collaborative effort to improve the coverage of 528:, a collaborative effort to improve the coverage of 270:, a collaborative effort to improve the coverage of 2262:
was more readable in order to grasp the context? --
433: 2215:? That's why I asked what made you think that SQL 1968: 1939: 1900: 1873: 1842: 1791: 1764: 1731: 1704: 1675: 1557: 1415: 1296: 1184: 826:Computer science articles needing expert attention 1058:, a project which is currently considered to be 33:for general discussion of the article's subject. 2199:need not be recursively defined (however, even 2105:as used in in the originally mathematical term 966:WikiProject Computer science/Unreferenced BLPs 1185:{\displaystyle L=\{a^{n}b^{n}c^{n}|n\geq 1\}} 174: 8: 1670: 1659: 1646: 1626: 1614: 1593: 1552: 1541: 1528: 1508: 1496: 1475: 1410: 1334: 1291: 1269: 1257: 1236: 1179: 1132: 883:Computer science articles without infoboxes 821:Computer science articles needing attention 188: 1492:is a regular expression over the alphabet 1018: 787:Here are some tasks awaiting attention: 761: 676: 579: 474: 430: 321: 216: 1952: 1928: 1916: 1892: 1886: 1865: 1859: 1831: 1804: 1783: 1777: 1772:is the length of its input. Thus the set 1756: 1744: 1723: 1717: 1696: 1690: 1662: 1639: 1629: 1607: 1584: 1578: 1544: 1521: 1511: 1489: 1466: 1460: 1396: 1385: 1377: 1364: 1349: 1341: 1332: 1282: 1272: 1250: 1234: 1165: 1159: 1149: 1139: 1124: 2436:Low-importance Computer science articles 2047:This article has inpenetrable complexity 1908:(cf. Theorem 2.1 in Stockmeyer/Meyer). 1668: 1596: 1550: 1478: 1289: 1239: 1070:Knowledge:WikiProject Cognitive science 1020: 678: 581: 476: 323: 218: 1073:Template:WikiProject Cognitive science 728:Knowledge:WikiProject Computer science 391:about philosophy content on Knowledge. 2441:WikiProject Computer science articles 2431:Start-Class Computer science articles 731:Template:WikiProject Computer science 7: 2195:, a programming language supporting 1054:This article is within the scope of 708:This article is within the scope of 611:This article is within the scope of 522:This article is within the scope of 375:This article is within the scope of 264:This article is within the scope of 2406:Low-importance Linguistics articles 207:It is of interest to the following 23:for discussing improvements to the 2381:Low-importance Philosophy articles 1117:Hopcroft & Ullman (1979 p.390) 902:Timeline of computing 2020–present 14: 2421:Low-importance Computing articles 2371:Low-priority mathematics articles 928:Computing articles needing images 542:Knowledge:WikiProject Linguistics 284:Knowledge:WikiProject Mathematics 2411:WikiProject Linguistics articles 2401:Start-Class Linguistics articles 2366:Start-Class mathematics articles 1047: 1022: 778: 701: 680: 604: 583: 545:Template:WikiProject Linguistics 509: 499: 478: 397:Knowledge:WikiProject Philosophy 362: 352: 325: 287:Template:WikiProject Mathematics 251: 241: 220: 189: 45:Click here to start a new topic. 2376:Start-Class Philosophy articles 1642:does not describe all words in 1524:does not describe all words in 748:This article has been rated as 659:This article has been rated as 639:Knowledge:WikiProject Computing 562:This article has been rated as 417:This article has been rated as 400:Template:WikiProject Philosophy 304:This article has been rated as 2416:Start-Class Computing articles 2042:23:41, 29 September 2009 (UTC) 1963: 1957: 1934: 1921: 1837: 1824: 1815: 1809: 1397: 1391: 1378: 1355: 1342: 1275:and the language described by 1166: 1103:(a^n)(b^n)(c^n) is recursive. 642:Template:WikiProject Computing 1: 2391:Low-importance logic articles 2014:00:43, 21 February 2008 (UTC) 2004:. Comments are very welcome. 1843:{\displaystyle O(m)=O(2^{n})} 1314:22:05, 28 February 2015 (UTC) 1218:19:35, 26 February 2015 (UTC) 1056:WikiProject Cognitive science 982:Tag all relevant articles in 722:and see a list of open tasks. 633:and see a list of open tasks. 536:and see a list of open tasks. 278:and see a list of open tasks. 42:Put new text under old text. 2207:, then get curious what the 2097:I guess you are thinking of 2002:Recursive languages and sets 1323:links I understand that the 1201:22:22, 8 November 2006 (UTC) 1108:17:39, 8 November 2006 (UTC) 991:WikiProject Computer science 767:WikiProject Computer science 711:WikiProject Computer science 2125:Lisp (programming language) 1765:{\displaystyle m\leq 2^{n}} 922:List of computer scientists 50:New to Knowledge? Welcome! 2457: 2386:Start-Class logic articles 2209:Recursive (disambiguation) 1990:22:26, 10 March 2015 (UTC) 1433:11:04, 10 March 2015 (UTC) 1076:Cognitive science articles 754:project's importance scale 665:project's importance scale 568:project's importance scale 423:project's importance scale 2396:Logic task force articles 2343:23:08, 18 June 2023 (UTC) 2322:06:20, 16 July 2011 (UTC) 2294:03:53, 16 July 2011 (UTC) 2272:21:19, 14 July 2011 (UTC) 2246:20:05, 13 July 2011 (UTC) 2117:13:28, 26 June 2011 (UTC) 2091:11:02, 26 June 2011 (UTC) 2081:about in this article. -- 2071:08:07, 25 June 2011 (UTC) 1042: 984:Category:Computer science 760: 747: 734:Computer science articles 696: 658: 599: 561: 494: 458: 429: 416: 347: 303: 236: 215: 80:Be welcoming to newcomers 2230:22:11, 4 July 2011 (UTC) 2179:09:59, 1 July 2011 (UTC) 2145:02:30, 1 July 2011 (UTC) 1940:{\displaystyle O(2^{n})} 986:and sub-categories with 310:project's priority scale 1980:which are tautologies. 1325:Space hierarchy theorem 525:WikiProject Linguistics 434:Associated task forces: 267:WikiProject Mathematics 2426:All Computing articles 1970: 1941: 1902: 1875: 1854:1', such that the set 1844: 1793: 1766: 1733: 1706: 1677: 1559: 1417: 1298: 1186: 947:Computer science stubs 627:information technology 455: 378:WikiProject Philosophy 197:This article is rated 75:avoid personal attacks 2163:context-free language 1978:Presburger arithmetic 1971: 1942: 1903: 1901:{\displaystyle c^{n}} 1876: 1874:{\displaystyle S_{2}} 1845: 1794: 1792:{\displaystyle S_{2}} 1767: 1734: 1732:{\displaystyle 2^{n}} 1707: 1705:{\displaystyle S_{2}} 1685:On one hand, the set 1678: 1560: 1418: 1299: 1187: 614:WikiProject Computing 454: 100:Neutral point of view 2193:recursive definition 2059:procedural languages 1969:{\displaystyle O(n)} 1951: 1915: 1885: 1858: 1803: 1776: 1743: 1716: 1689: 1577: 1459: 1331: 1319:Thank you. From the 1233: 1123: 765:Things you can help 548:Linguistics articles 290:mathematics articles 105:No original research 403:Philosophy articles 2107:recursive language 1966: 1937: 1898: 1871: 1840: 1789: 1762: 1729: 1702: 1673: 1669: 1644: 1634: 1612: 1597: 1555: 1551: 1526: 1516: 1494: 1479: 1413: 1294: 1290: 1287: 1277: 1255: 1240: 1182: 645:Computing articles 517:Linguistics portal 456: 388:general discussion 259:Mathematics portal 203:content assessment 86:dispute resolution 47: 25:Recursive language 2201:regular languages 2099:recursive queries 1643: 1633: 1611: 1525: 1515: 1493: 1286: 1276: 1254: 1092: 1091: 1088: 1087: 1084: 1083: 1067:Cognitive science 1030:Cognitive science 1017: 1016: 1013: 1012: 1009: 1008: 1005: 1004: 675: 674: 671: 670: 578: 577: 574: 573: 473: 472: 469: 468: 465: 464: 370:Philosophy portal 320: 319: 316: 315: 183: 182: 66:Assume good faith 43: 2448: 2188:Spanish language 2171:Tobias Bergemann 2159:regular language 2155:formal languages 1995:Attempt to merge 1975: 1973: 1972: 1967: 1946: 1944: 1943: 1938: 1933: 1932: 1907: 1905: 1904: 1899: 1897: 1896: 1880: 1878: 1877: 1872: 1870: 1869: 1849: 1847: 1846: 1841: 1836: 1835: 1798: 1796: 1795: 1790: 1788: 1787: 1771: 1769: 1768: 1763: 1761: 1760: 1738: 1736: 1735: 1730: 1728: 1727: 1711: 1709: 1708: 1703: 1701: 1700: 1682: 1680: 1679: 1674: 1667: 1666: 1645: 1641: 1635: 1631: 1613: 1609: 1589: 1588: 1564: 1562: 1561: 1556: 1549: 1548: 1527: 1523: 1517: 1513: 1495: 1491: 1471: 1470: 1425:Jochen Burghardt 1422: 1420: 1419: 1414: 1400: 1395: 1394: 1390: 1389: 1372: 1371: 1359: 1358: 1354: 1353: 1303: 1301: 1300: 1295: 1288: 1284: 1278: 1274: 1256: 1252: 1210:Jochen Burghardt 1191: 1189: 1188: 1183: 1169: 1164: 1163: 1154: 1153: 1144: 1143: 1078: 1077: 1074: 1071: 1068: 1051: 1044: 1043: 1038: 1026: 1019: 995: 989: 864:Computer science 793:Article requests 782: 775: 774: 762: 736: 735: 732: 729: 726: 725:Computer science 716:Computer science 705: 698: 697: 692: 688:Computer science 684: 677: 647: 646: 643: 640: 637: 608: 601: 600: 595: 587: 580: 550: 549: 546: 543: 540: 519: 514: 513: 503: 496: 495: 490: 482: 475: 441: 431: 405: 404: 401: 398: 395: 372: 367: 366: 365: 356: 349: 348: 343: 340: 329: 322: 292: 291: 288: 285: 282: 261: 256: 255: 245: 238: 237: 232: 224: 217: 200: 194: 193: 185: 179: 178: 164: 95:Article policies 16: 2456: 2455: 2451: 2450: 2449: 2447: 2446: 2445: 2356: 2355: 2312:formal language 2049: 2021: 1997: 1949: 1948: 1924: 1913: 1912: 1888: 1883: 1882: 1861: 1856: 1855: 1827: 1801: 1800: 1779: 1774: 1773: 1752: 1741: 1740: 1719: 1714: 1713: 1692: 1687: 1686: 1658: 1580: 1575: 1574: 1540: 1462: 1457: 1456: 1445:and the survey 1381: 1373: 1360: 1345: 1337: 1329: 1328: 1231: 1230: 1155: 1145: 1135: 1121: 1120: 1097: 1075: 1072: 1069: 1066: 1065: 1032: 1001: 998: 993: 987: 975:Project-related 970: 951: 932: 906: 887: 868: 849: 830: 806: 733: 730: 727: 724: 723: 690: 644: 641: 638: 635: 634: 593: 547: 544: 541: 538: 537: 515: 508: 488: 439: 402: 399: 396: 393: 392: 368: 363: 361: 341: 335: 289: 286: 283: 280: 279: 257: 250: 230: 201:on Knowledge's 198: 121: 116: 115: 114: 91: 61: 12: 11: 5: 2454: 2452: 2444: 2443: 2438: 2433: 2428: 2423: 2418: 2413: 2408: 2403: 2398: 2393: 2388: 2383: 2378: 2373: 2368: 2358: 2357: 2354: 2353: 2352: 2351: 2350: 2349: 2348: 2347: 2346: 2345: 2332: 2328: 2301: 2300: 2299: 2298: 2297: 2296: 2277: 2276: 2275: 2274: 2260:recursive sets 2249: 2248: 2213:recursive sets 2184: 2183: 2182: 2181: 2148: 2147: 2120: 2119: 2094: 2093: 2048: 2045: 2020: 2017: 1996: 1993: 1965: 1962: 1959: 1956: 1936: 1931: 1927: 1923: 1920: 1895: 1891: 1868: 1864: 1839: 1834: 1830: 1826: 1823: 1820: 1817: 1814: 1811: 1808: 1786: 1782: 1759: 1755: 1751: 1748: 1726: 1722: 1699: 1695: 1672: 1665: 1661: 1657: 1654: 1651: 1648: 1638: 1628: 1625: 1622: 1619: 1616: 1606: 1603: 1600: 1595: 1592: 1587: 1583: 1554: 1547: 1543: 1539: 1536: 1533: 1530: 1520: 1510: 1507: 1504: 1501: 1498: 1488: 1485: 1482: 1477: 1474: 1469: 1465: 1451: 1450: 1443: 1442: 1412: 1409: 1406: 1403: 1399: 1393: 1388: 1384: 1380: 1376: 1370: 1367: 1363: 1357: 1352: 1348: 1344: 1340: 1336: 1317: 1316: 1293: 1281: 1271: 1268: 1265: 1262: 1259: 1249: 1246: 1243: 1238: 1206: 1205: 1204: 1203: 1181: 1178: 1175: 1172: 1168: 1162: 1158: 1152: 1148: 1142: 1138: 1134: 1131: 1128: 1111: 1110: 1105:128.84.152.179 1096: 1093: 1090: 1089: 1086: 1085: 1082: 1081: 1079: 1052: 1040: 1039: 1027: 1015: 1014: 1011: 1010: 1007: 1006: 1003: 1002: 1000: 999: 997: 996: 979: 971: 969: 968: 962: 952: 950: 949: 943: 933: 931: 930: 925: 917: 907: 905: 904: 898: 888: 886: 885: 879: 869: 867: 866: 860: 850: 848: 847: 841: 831: 829: 828: 823: 817: 807: 805: 804: 798: 786: 784: 783: 771: 770: 758: 757: 750:Low-importance 746: 740: 739: 737: 720:the discussion 706: 694: 693: 691:Low‑importance 685: 673: 672: 669: 668: 661:Low-importance 657: 651: 650: 648: 631:the discussion 609: 597: 596: 594:Low‑importance 588: 576: 575: 572: 571: 564:Low-importance 560: 554: 553: 551: 534:the discussion 521: 520: 504: 492: 491: 489:Low‑importance 483: 471: 470: 467: 466: 463: 462: 457: 447: 446: 444: 442: 436: 435: 427: 426: 419:Low-importance 415: 409: 408: 406: 374: 373: 357: 345: 344: 342:Low‑importance 330: 318: 317: 314: 313: 302: 296: 295: 293: 276:the discussion 263: 262: 246: 234: 233: 225: 213: 212: 206: 195: 181: 180: 118: 117: 113: 112: 107: 102: 93: 92: 90: 89: 82: 77: 68: 62: 60: 59: 48: 39: 38: 35: 34: 28: 13: 10: 9: 6: 4: 3: 2: 2453: 2442: 2439: 2437: 2434: 2432: 2429: 2427: 2424: 2422: 2419: 2417: 2414: 2412: 2409: 2407: 2404: 2402: 2399: 2397: 2394: 2392: 2389: 2387: 2384: 2382: 2379: 2377: 2374: 2372: 2369: 2367: 2364: 2363: 2361: 2344: 2340: 2336: 2333: 2329: 2325: 2324: 2323: 2320: 2317: 2313: 2309: 2308: 2307: 2306: 2305: 2304: 2303: 2302: 2295: 2291: 2287: 2283: 2282: 2281: 2280: 2279: 2278: 2273: 2269: 2265: 2264:Zahnradzacken 2261: 2257: 2253: 2252: 2251: 2250: 2247: 2243: 2239: 2234: 2233: 2232: 2231: 2227: 2223: 2222:Zahnradzacken 2218: 2214: 2210: 2206: 2202: 2198: 2194: 2189: 2180: 2176: 2172: 2168: 2164: 2160: 2156: 2152: 2151: 2150: 2149: 2146: 2142: 2138: 2134: 2130: 2126: 2122: 2121: 2118: 2115: 2112: 2108: 2104: 2100: 2096: 2095: 2092: 2088: 2084: 2083:Zahnradzacken 2079: 2075: 2074: 2073: 2072: 2068: 2064: 2060: 2055: 2046: 2044: 2043: 2039: 2035: 2031: 2028: 2024: 2018: 2016: 2015: 2011: 2007: 2003: 1994: 1992: 1991: 1987: 1983: 1979: 1960: 1954: 1929: 1925: 1918: 1909: 1893: 1889: 1866: 1862: 1851: 1832: 1828: 1821: 1818: 1812: 1806: 1784: 1780: 1757: 1753: 1749: 1746: 1724: 1720: 1697: 1693: 1683: 1663: 1655: 1652: 1649: 1636: 1623: 1620: 1617: 1604: 1601: 1598: 1590: 1585: 1581: 1572: 1568: 1565: 1545: 1537: 1534: 1531: 1518: 1505: 1502: 1499: 1486: 1483: 1480: 1472: 1467: 1463: 1454: 1448: 1447: 1446: 1440: 1439: 1438: 1435: 1434: 1430: 1426: 1407: 1404: 1401: 1386: 1382: 1374: 1368: 1365: 1361: 1350: 1346: 1338: 1326: 1322: 1321:stackexchange 1315: 1311: 1307: 1279: 1266: 1263: 1260: 1247: 1244: 1241: 1228: 1225: 1222: 1221: 1220: 1219: 1215: 1211: 1202: 1199: 1195: 1176: 1173: 1170: 1160: 1156: 1150: 1146: 1140: 1136: 1129: 1126: 1118: 1115: 1114: 1113: 1112: 1109: 1106: 1102: 1101: 1100: 1094: 1080: 1063: 1062: 1057: 1053: 1050: 1046: 1045: 1041: 1036: 1031: 1028: 1025: 1021: 992: 985: 981: 980: 978: 976: 972: 967: 964: 963: 961: 959: 958: 953: 948: 945: 944: 942: 940: 939: 934: 929: 926: 923: 919: 918: 916: 914: 913: 908: 903: 900: 899: 897: 895: 894: 889: 884: 881: 880: 878: 876: 875: 870: 865: 862: 861: 859: 857: 856: 851: 846: 843: 842: 840: 838: 837: 832: 827: 824: 822: 819: 818: 816: 814: 813: 808: 803: 800: 799: 797: 795: 794: 789: 788: 785: 781: 777: 776: 773: 772: 768: 764: 763: 759: 755: 751: 745: 742: 741: 738: 721: 717: 713: 712: 707: 704: 700: 699: 695: 689: 686: 683: 679: 666: 662: 656: 653: 652: 649: 632: 628: 624: 620: 616: 615: 610: 607: 603: 602: 598: 592: 589: 586: 582: 569: 565: 559: 556: 555: 552: 535: 531: 527: 526: 518: 512: 507: 505: 502: 498: 497: 493: 487: 484: 481: 477: 461: 453: 449: 448: 445: 443: 438: 437: 432: 428: 424: 420: 414: 411: 410: 407: 390: 389: 384: 380: 379: 371: 360: 358: 355: 351: 350: 346: 339: 334: 331: 328: 324: 311: 307: 301: 298: 297: 294: 277: 273: 269: 268: 260: 254: 249: 247: 244: 240: 239: 235: 229: 226: 223: 219: 214: 210: 204: 196: 192: 187: 186: 177: 173: 170: 167: 163: 159: 155: 152: 149: 146: 143: 140: 137: 134: 131: 127: 124: 123:Find sources: 120: 119: 111: 110:Verifiability 108: 106: 103: 101: 98: 97: 96: 87: 83: 81: 78: 76: 72: 69: 67: 64: 63: 57: 53: 52:Learn to edit 49: 46: 41: 40: 37: 36: 32: 26: 22: 18: 17: 2335:Mike-c-in-mv 2255: 2216: 2185: 2106: 2102: 2098: 2077: 2050: 2032: 2029: 2025: 2022: 1998: 1910: 1852: 1684: 1573: 1569: 1566: 1455: 1452: 1444: 1436: 1320: 1318: 1207: 1098: 1059: 974: 973: 957:Unreferenced 955: 954: 936: 935: 910: 909: 891: 890: 872: 871: 853: 852: 834: 833: 810: 809: 791: 790: 749: 709: 660: 612: 563: 523: 418: 386: 376: 306:Low-priority 305: 265: 231:Low‑priority 209:WikiProjects 171: 165: 157: 150: 144: 138: 132: 122: 94: 19:This is the 1119:state that 539:Linguistics 530:linguistics 486:Linguistics 281:Mathematics 272:mathematics 228:Mathematics 199:Start-class 148:free images 31:not a forum 2360:Categories 1947:and space 394:Philosophy 383:philosophy 333:Philosophy 2205:recursion 2197:recursion 2167:recursion 2129:Smalltalk 2103:recursive 1198:jonsafari 845:Computing 636:Computing 623:computing 619:computers 591:Computing 88:if needed 71:Be polite 21:talk page 2157:(as in “ 2006:Pichpich 1285:is empty 1061:inactive 1035:inactive 893:Maintain 836:Copyedit 56:get help 29:This is 27:article. 1194:indexed 1095:Example 874:Infobox 812:Cleanup 752:on the 663:on the 566:on the 421:on the 308:on the 154:WP refs 142:scholar 2286:Jarhed 2238:Jarhed 2137:Jarhed 2063:Jarhed 2019:Revert 1982:Hermel 1306:Hermel 855:Expand 625:, and 205:scale. 126:Google 2331:list. 2319:Adler 2114:Adler 2034:Misof 938:Stubs 912:Photo 769:with: 460:Logic 338:Logic 169:JSTOR 130:books 84:Seek 2339:talk 2316:Hans 2290:talk 2268:talk 2242:talk 2226:talk 2175:talk 2161:”, “ 2141:talk 2131:and 2111:Hans 2087:talk 2067:talk 2038:talk 2010:talk 1986:talk 1632:and 1514:and 1429:talk 1310:talk 1214:talk 162:FENS 136:news 73:and 2133:SQL 2054:SQL 1192:is 744:Low 655:Low 558:Low 413:Low 300:Low 176:TWL 2362:: 2341:) 2314:. 2292:) 2270:) 2244:) 2228:) 2220:-- 2217:is 2177:) 2143:) 2127:, 2089:) 2078:is 2069:) 2040:) 2012:) 1988:) 1850:. 1750:≤ 1664:∗ 1602:∣ 1546:∗ 1484:∣ 1431:) 1405:≥ 1312:) 1245:∣ 1216:) 1174:≥ 994:}} 988:{{ 621:, 440:/ 336:: 156:) 54:; 2337:( 2288:( 2266:( 2256:a 2240:( 2224:( 2173:( 2139:( 2085:( 2065:( 2036:( 2008:( 1984:( 1964:) 1961:n 1958:( 1955:O 1935:) 1930:n 1926:2 1922:( 1919:O 1894:n 1890:c 1867:2 1863:S 1838:) 1833:n 1829:2 1825:( 1822:O 1819:= 1816:) 1813:m 1810:( 1807:O 1785:2 1781:S 1758:n 1754:2 1747:m 1725:n 1721:2 1698:2 1694:S 1671:} 1660:} 1656:b 1653:, 1650:a 1647:{ 1637:r 1627:} 1624:b 1621:, 1618:a 1615:{ 1605:r 1599:r 1594:{ 1591:= 1586:2 1582:S 1553:} 1542:} 1538:b 1535:, 1532:a 1529:{ 1519:r 1509:} 1506:b 1503:, 1500:a 1497:{ 1487:r 1481:r 1476:{ 1473:= 1468:1 1464:S 1427:( 1411:} 1408:1 1402:n 1398:| 1392:) 1387:2 1383:n 1379:( 1375:c 1369:! 1366:n 1362:b 1356:) 1351:n 1347:2 1343:( 1339:a 1335:{ 1308:( 1292:} 1280:r 1270:} 1267:b 1264:, 1261:a 1258:{ 1248:r 1242:r 1237:{ 1212:( 1180:} 1177:1 1171:n 1167:| 1161:n 1157:c 1151:n 1147:b 1141:n 1137:a 1133:{ 1130:= 1127:L 1064:. 1037:) 1033:( 977:: 960:: 941:: 924:) 915:: 896:: 877:: 858:: 839:: 815:: 796:: 756:. 667:. 570:. 425:. 312:. 211:: 172:· 166:· 158:· 151:· 145:· 139:· 133:· 128:( 58:.

Index

talk page
Recursive language
not a forum
Click here to start a new topic.
Learn to edit
get help
Assume good faith
Be polite
avoid personal attacks
Be welcoming to newcomers
dispute resolution
Neutral point of view
No original research
Verifiability
Google
books
news
scholar
free images
WP refs
FENS
JSTOR
TWL

content assessment
WikiProjects
WikiProject icon
Mathematics
WikiProject icon
icon

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