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Talk:Arithmetical hierarchy

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264: 254: 233: 200: 2084:, rather than just putting in a sentence about how the same concepts can be interpreted either on the reals or on the naturals. The thing is, I don't really think of this as computability, but as descriptive set theory, and I would have probably done the writeup for the concept on the naturals as descriptive set theory as well. But the computability-theory concepts are important and should be there, which complicates the presentation. -- 191: 342: 3138:
The article previously contained the claim that any formula with bounded quantifiers is equivalent to a quantifier-free formula. There was a "citation needed" comment questioning this claim, and it is indeed false, so I removed it. I just wanted to record a counter-example here (there may be simpler
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See Kozen - Theory of Computation (pp. 239-246) for natural complete problems in the Arithmetic Hierarchy of sets of natural numbers. That is EMPTY for \Pi^0_1, the halting Problem for \Sigma^0_1, TOTAL for \Pi^0_2, FIN(ITE) for \Sigma^0_2 and COF(FINITE) for \Sigma^0_3. These are all index sets and
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Examples: Sigma_1-complete to determine halting/looping of encoded Turing machines. Pi_2 complete to determine if encoded TMs accept an infinite set. Sigma_3-complete to determine if TM accepts a recursive set. Pi_3-complete to determine if TM encodes a walk that diverges properly to infinity.
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It would be great if we had a NavBox of all the different hierarchies: polynomial hierarchy, weak exponential hierarchy, arithmethical hierarchy, hyperarithmetical hierarchy, and the ones shown here. The current NavBox (at the bottom) could be expanded. Assuming P≠NP≠PH, a NavBox could look like
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The translation from the french is kind of rough, and the french version has either been taken offline (it was published as a printed book a couple years ago) or was never there, but anyway I can't compare the two as a result. Thanks for trying to decipher the english version. I thought maybe
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Indeed, I made some typos which I corrected. But you are correct, I am a bit confused. I have not dealt with computability structure on uncountable sets before. What I was trying to get at was that there must be some sort of countable structure underneath the real number system (in some sense).
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of the objects you're quantifying over: Type 0 objects are naturals, type 1 objects are sets of naturals, or functions from the naturals to the naturals, or reals; type 2 objects are sets of sets of naturals, or functions from the reals to the reals, or sets of reals, or.... In general a
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I worked these out and they need checking. They are important to have around, because classifying the hierarchy level of a set almost invariably involves showing it complete for that level, and one needs a variety of target problems to work with just like with NP-completeness.
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Wouldn't it be more useful to have a navbox of the complexity classes adjacent to the specific hierarchy in question (e.g., P ⊆ PH ⊆ PSPACE on the PH page)? Beyond the fact that they are all hierarchies, PH, EXPH, and AH belong to very different positions in complexity space.
5233:. Since the topological notion is probably more familiar to many readers, the sentence as it stands is likely to create confusion. Using the term "Baire space (set theory)" would alert readers to the fact that the topological notion is not the one being referred to here. 450:. I think MathMartin is thinking of sets of naturals, but the same concepts and notation are important for sets of reals (subsets of Baire space, Cantor space, general Polish spaces). Unfortunately finding good language for that is awkward. -- 2966:
I have a general sense that the "-al" versions of "arithmetical hierarchy" and "hyperarithmetical hierarchy" are more common. I don't think "analytic hierarchy" is used at all. So I have restored the original endings here. — Carl
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I just noticed we were editing the page nearly in parallel :). Yes I am indeed thinking about sets of naturals and computable functions. What do you mean by arithmetical hierarchy for sets of reals ? Can you not just use a
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Are you saying you want to put the sets in a certain topological space in some sort of hierarchy according to how difficult they are to construct using the countable basis of the space ? In your hierarchy what are the
2037:; this is all completely standard and is standardly called the arithmetical hierarchy for sets of reals (see Moschovakis). The problem is how to convey the concepts in the article without making a mess of it. -- 3245: 2164:
Yep. There are all kinds of problems with this article. It's one of the ones I've got on my fix-up-someday list, but it looks like sort of an unpleasant job, so the expected time before I get to it is long.
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Hmmm. Actually, I think the article is pretty broken at the moment. It's on my "to fix" list, but it'll take time because I'll need to re-read material on the subject. Feel free to beat me to it :) --
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Anyway thanks for the explanation. If you think the concepts you are talking about will mess up the article perhaps it would be best to start a new one. I would certainly like to read it. Cheers.
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sets. That is, there's a computable way of putting indices for basic open sets into an infinite square matrix, intersecting the basic open sets in each row, and then unioning up all the resulting
3344: 1860: 1568:. That is, there's a computable way of assigning all at once a collection of "rows" of basic open sets whose union is the complement of each rational's singleton, and then unioning all those up. 320: 2344:
their names are rather self-explanatory. The halting problem is well-known and the names of the other ones refer to the property of the domains of the functions with the respective index.
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The Knowledge entry on "Baire space" which is linked to here deals with the topological notion of a Baire space. Correct me if I am wrong, but I think the link should be to
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Furthermore, it seems that what Girard calls the "projective hierarchy" is actually the analytical hierarchy (i.e., lightface), but that does not make much difference here.—
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using the definition which is worked with in this article (it is not the case if one works with the other definition which might be why this result is quoted only for
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what the superscript means, rather than merely complaining about something you know how to fix yourself, here's a quick-and-dirty explanation: When we write Σ
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I believe the "Extensions and variations" sections mentions two alternatives but it's not clear that these are in fact two different alternatives.
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Would someone include some natural complete problems for the Arithmetic Hierarchy (of sets of natural numbers)? Same goes for Analytic Hierarchy.
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set of reals is "effectively open"; that is, there's a computable collection of indices for basic open sets, the union of which is the given set. A
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Well done! Thanks for correcting the record. This claim looked very fishy to me as well but I didn't put in the time to find a counterexample.
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is the collection of open sets which forms the countable basis of your topology. This numbering has to be choosen in such a way that your
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formulas, it thus corresponds to the projective hierarchy rather than the arithmetical hierarchy. According to Girard's examples, every
2497: 2328: 2291: 3177: 3067:, which I think is something like "lightface projective", but the risk of confusion is so great that it's probably better avoided. -- 474:
Not quite sure what you mean by that. The spaces I'm interested in are of course uncountable, though their topologies have countable
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The article doesn't explain the meaning of the zero superscript. Even if you are lucky enough to click through to the article on
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is either finite or has finite complement. Since this property is preserved by finite unions and intersections, it follows that
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Thanks for the explanation -- no, I did not know the answer or how to fix it. I've tried to fix it based on your explanation.--
2154:, there's still not much explanation of the relationship between the two articles or the meaning of the superscripts 0 and 1.-- 1768:
of your topology. This map is not a numbering because it is not surjective. The problem consists in finding a countable subset
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tells you the number of alternating quantifiers (starting with existential if it's Σ or universal if it's Π). The superscript
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to transfer the computability concept (an the arithmetical hierarchy) defined on the natural numbers to any other structure ?
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There's apparently an alternate expression called the "logic hierarchy", described in Girard's "The Blind Spot" p. 45-46
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but a computability concept, which then should allow you to build a new hierarchy similar to the arithmetical hierarchy.
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is pronounced “sigma one zero” or “sigma zero one”. I think saying which it is would be a helpful and easy addition.
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Thanks to MathMartin for putting in some useful stuff. The big problem left with this article, and also with
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I took some time this morning to substantially rework this article. I tried to fix the following problems.
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Moreover for the recursive/computable definition I believe it only differs from the usual definition for
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When you do, please define \Delta _{n}^{0}, that would help make the article much more comprehensible.
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there are plenty. To make the discussion useful on the "real reals" it's better not to start with
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on Knowledge. If you would like to participate, please visit the project page, where you can join
4755: 4451: 4207: 3689: 2496:. I won't add this myself since probably I don't have it right, but maybe it's worth a mention. 2118: 1725: 1632: 1574: 1513: 1491: 1452: 1394: 1372: 1307: 269: 70: 4827: 4692: 4523: 4388: 4059: 3823: 3666: 2369: 803: 253: 232: 4034: 3742: 3715: 3456: 3429: 3273: 374:
Please help fix the broken anchors. You can remove this template after fixing the problems. |
51: 4855: 4551: 4241: 3512: 3483: 2564: 2434: 5124: 5099: 5078: 5057: 4927: 4906: 4885: 2924: 868:'s, not just basic opens. So we actually need to start by computably filling up an infinite 354: 5121:(I've put the question mark above PSPACE since we could also consider ordinals larger than 3541: 2364: 4122: 3405: 3382: 3250: 2694: 2682: 2258:
The article had factual errors, such as the claim that Sigma^0_0 is the same as recursive.
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The article was not precise about the fact that the AH classifies sets of natural numbers.
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sets are exactly the recursively enumerable set in the computability concept induced by
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No, at least not literally. Maybe you made a typo, but of course such a countable
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As someone with only passing familiarity of this area, I can't remember whether
282: 1219:. The numbering does not directly induce the arithmetical hierarchy on the set 2691: 2679: 660: 259: 2638:(don't ask me why). In particular, all of arithmetical hierarchy fits inside 836:
Whoops--actually I skipped a step here. Along each row you need to intersect
3120: 2888:{\displaystyle \Sigma _{n}^{0}\cup \Pi _{n}^{0}\subsetneq \Delta _{n+1}^{0}} 663:; in the real numbers strictly speaking there are only two of these, but in 2519:—WTF???), but one thing is certain, namely that it is a stratification of 4342: 2970: 403: 4027: 2255:
The article was not precise about what language the formulas come from.
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Hmm, now I think I understand the problem. You want to construct a map
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This article links to one or more target anchors that no longer exist.
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I'm not sure if I'm understanding you. By a "computability concept on
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possibly conflating this article with any analytical hierarchy article
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of all even numbers cannot be defined by a quantifier-free formula
2393:(with no subscript) in the logic hierarchy means the same thing as 4161: 2106:
I am not an expert on this topic so I might be missing something.
3240:{\displaystyle X=\{n\in \mathbb {N} \mid \exists k\leq n(2k=n)\}} 2080:. I'm coming to the conclusion that it probably needs a separate 5177: 884:
My understanding (what I meant to say) is you need a numbering
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which you can use to construct the collection of "effectively F
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with indices for basic opens. Details left as an exercise. --
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The hierarchy does not collapse; which I think is from Kleene
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sets are the ones that are the effective counterpart of the
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Maybe an example would help focus things. Consider the set
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to mention both subsets of N and subsets of Baire space.
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I know it's a lot to read, but 13 years is a bit much ;)
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are exactly the recursively enumerable sets. Correct ?
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is an open set in the usual topology on the space."
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And there isn't actually any 1008:Pretty much, but that doesn't take you past 2125:, which doesn't actually define the term.-- 3977:{\displaystyle {\overset {?}{\subseteq }}} 3881: 3867: 3134:Bounded quantifiers versus quantifier-free 2703:"logic hierarchy" was some standard term. 422: 227: 5157: 5152: 5146: 5126: 5101: 5080: 5059: 5035: 5029: 5000: 4995: 4989: 4963: 4958: 4952: 4929: 4908: 4887: 4863: 4857: 4835: 4829: 4801: 4796: 4790: 4768: 4763: 4757: 4735: 4730: 4724: 4700: 4694: 4666: 4661: 4655: 4627: 4622: 4616: 4594: 4589: 4583: 4559: 4553: 4531: 4525: 4497: 4492: 4486: 4464: 4459: 4453: 4431: 4426: 4420: 4396: 4390: 4362: 4357: 4351: 4317: 4312: 4306: 4284: 4279: 4273: 4249: 4243: 4215: 4209: 4181: 4176: 4170: 4142: 4137: 4131: 4103: 4098: 4092: 4067: 4061: 4039: 4038: 4036: 4002: 3997: 3991: 3964: 3962: 3934: 3929: 3923: 3800: 3794: 3774: 3750: 3744: 3723: 3717: 3691: 3668: 3639: 3616: 3579: 3543: 3514: 3485: 3464: 3458: 3437: 3431: 3407: 3384: 3363: 3351: 3314: 3313: 3302: 3281: 3275: 3252: 3197: 3196: 3179: 3158: 3153: 3147: 3103: 3098: 3092: 3049:{\displaystyle \Sigma _{<\omega }^{1}} 3040: 3032: 3026: 3005: 3000: 2994: 2926: 2900: 2879: 2868: 2855: 2850: 2837: 2832: 2826: 2802: 2797: 2791: 2770: 2765: 2759: 2733: 2662: 2649: 2643: 2622: 2617: 2604: 2598: 2572: 2566: 2545: 2534: 2528: 2511:I don't understand Girard's description ( 2480: 2469: 2463: 2442: 2436: 2415: 2404: 2398: 2377: 2371: 2076:I hardly think it needs a whole separate 2017: 2012: 2006: 1985: 1980: 1974: 1954: 1934: 1904: 1903: 1901: 1876: 1875: 1867: 1834: 1833: 1822: 1801: 1800: 1799: 1793: 1773: 1752: 1751: 1749: 1730: 1729: 1727: 1706: 1705: 1704: 1691: 1690: 1689: 1677: 1637: 1636: 1634: 1613: 1608: 1602: 1579: 1578: 1576: 1548: 1543: 1537: 1518: 1517: 1515: 1496: 1495: 1493: 1465: 1460: 1454: 1427: 1426: 1418: 1399: 1398: 1396: 1377: 1376: 1374: 1334: 1333: 1331: 1312: 1311: 1309: 1288: 1287: 1285: 1260: 1259: 1257: 1227: 1226: 1224: 1203: 1202: 1194: 1174: 1153: 1148: 1142: 1117: 1116: 1114: 1094: 1056: 1051: 1045: 1024: 1019: 1013: 989: 968: 963: 957: 936: 935: 933: 909: 908: 901: 900: 892: 852: 847: 841: 811: 805: 781: 775: 754: 749: 743: 719: 714: 708: 687: 682: 676: 643: 638: 632: 607: 602: 596: 575: 570: 564: 526: 521: 515: 494: 489: 483: 389:We need the following interesting facts: 2671:{\displaystyle \Pi ^{2}\cap \Sigma ^{2}} 2631:{\displaystyle \Pi ^{1}=\Sigma _{1}^{0}} 2593:1, while the next section suggests that 1391:of all rational numbers, as a subset of 5267:Knowledge vital articles in Mathematics 5015:{\displaystyle \Delta _{\omega }^{EXP}} 3789:does not have this property, and hence 3060:in the sense of "projective hierarchy". 1629:collection of basic open sets, because 229: 188: 4975:{\displaystyle \Delta _{\omega }^{P}=} 1889:{\displaystyle \nu :\mathbb {N} \to X} 1276:", do you mean a notion of computable 5282:B-Class vital articles in Mathematics 2276:I am planning to edit this page like 1109:induces a computability structure on 7: 3538:is equivalent either to the formula 2261:I added a reference to Rogers' book. 659:sets could be taken to be the basic 591:sets (is this your basis ?) and the 275:This article is within the scope of 3663:is either constant or tends toward 2431:from the arithmetic hierarchy, and 1212:{\displaystyle B\in {\mathcal {B}}} 218:It is of interest to the following 23:for discussing improvements to the 5032: 4992: 4955: 4860: 4832: 4793: 4760: 4727: 4697: 4658: 4619: 4586: 4556: 4528: 4489: 4456: 4423: 4393: 4354: 4335:{\displaystyle \Sigma _{1}^{EXP}=} 4309: 4276: 4246: 4212: 4173: 4134: 4095: 4064: 4020:{\displaystyle \Delta _{0}^{EXP}=} 3994: 3926: 3699: 3673: 3204: 3150: 3095: 3029: 2997: 2865: 2847: 2829: 2794: 2762: 2659: 2646: 2614: 2601: 2569: 2531: 2466: 2439: 2401: 2374: 2009: 1977: 1824: 1605: 1540: 1457: 1145: 1072:set of naturals, you still get an 1048: 1016: 960: 844: 793:{\displaystyle G_{\delta \sigma }} 746: 711: 679: 635: 599: 567: 518: 486: 14: 5292:Mid-priority mathematics articles 5044:{\displaystyle \Delta _{\omega }} 4816:{\displaystyle \Delta _{3}^{EXP}} 4642:{\displaystyle \Sigma _{2}^{EXP}} 4512:{\displaystyle \Delta _{2}^{EXP}} 4196:{\displaystyle \Delta _{1}^{EXP}} 2489:{\displaystyle \Sigma _{n-1}^{0}} 2001:sets of basic open sets. We want 1949:can't exist, because each of the 1434:{\displaystyle q\in \mathbb {Q} } 295:Knowledge:WikiProject Mathematics 5262:Knowledge level-5 vital articles 5169:{\displaystyle \omega _{1}^{CK}} 4115:{\displaystyle \Sigma _{1}^{P}=} 3946:{\displaystyle \Delta _{0}^{P}=} 3063:There is a separate meaning for 1810:{\displaystyle 2^{\mathbb {R} }} 463:numbering (computability theory) 340: 298:Template:WikiProject Mathematics 262: 252: 231: 198: 189: 45:Click here to start a new topic. 4744:{\displaystyle \Sigma _{3}^{P}} 4603:{\displaystyle \Delta _{2}^{P}} 4440:{\displaystyle \Sigma _{2}^{P}} 4293:{\displaystyle \Delta _{1}^{P}} 3815:{\displaystyle X_{\phi }\neq X} 3372:{\displaystyle X\neq X_{\phi }} 3167:{\displaystyle \Delta _{0}^{0}} 3112:{\displaystyle \Sigma _{1}^{0}} 3014:{\displaystyle \Sigma _{1}^{1}} 2811:{\displaystyle \Delta _{1}^{0}} 2779:{\displaystyle \Delta _{0}^{0}} 2026:{\displaystyle \Sigma _{n}^{0}} 1994:{\displaystyle \Sigma _{n}^{0}} 1622:{\displaystyle \Sigma _{2}^{0}} 1557:{\displaystyle \Sigma _{2}^{0}} 1162:{\displaystyle \Sigma _{2}^{0}} 1065:{\displaystyle \Sigma _{2}^{0}} 1033:{\displaystyle \Sigma _{1}^{0}} 977:{\displaystyle \Sigma _{1}^{0}} 861:{\displaystyle \Sigma _{1}^{0}} 763:{\displaystyle \Sigma _{3}^{0}} 728:{\displaystyle \Sigma _{1}^{0}} 696:{\displaystyle \Sigma _{0}^{0}} 652:{\displaystyle \Sigma _{0}^{0}} 616:{\displaystyle \Sigma _{3}^{0}} 584:{\displaystyle \Sigma _{0}^{0}} 535:{\displaystyle \Sigma _{2}^{0}} 503:{\displaystyle \Sigma _{1}^{0}} 315:This article has been rated as 5272:B-Class level-5 vital articles 5176:(for which it has been proven 4681:{\displaystyle \Pi _{2}^{EXP}} 4377:{\displaystyle \Pi _{1}^{EXP}} 3696: 3650: 3644: 3590: 3584: 3554: 3548: 3525: 3519: 3496: 3490: 3330: 3324: 3231: 3216: 3129:10:16, 21 September 2020 (UTC) 2957:14:13, 30 September 2014 (UTC) 2554:{\displaystyle \Pi _{n-1}^{1}} 2424:{\displaystyle \Pi _{n-1}^{0}} 2089:22:08, 24 September 2005 (UTC) 2072:22:02, 24 September 2005 (UTC) 2042:21:42, 24 September 2005 (UTC) 1925:21:34, 24 September 2005 (UTC) 1913:{\displaystyle {\mathcal {B}}} 1880: 1761:{\displaystyle {\mathcal {B}}} 1744:to the open sets in the basis 1697: 1656:21:01, 24 September 2005 (UTC) 1355:20:47, 24 September 2005 (UTC) 1343:{\displaystyle {\mathcal {B}}} 1297:{\displaystyle {\mathcal {B}}} 1269:{\displaystyle {\mathcal {B}}} 1248:20:37, 24 September 2005 (UTC) 1236:{\displaystyle {\mathcal {B}}} 1126:{\displaystyle {\mathcal {B}}} 1081:18:45, 24 September 2005 (UTC) 945:{\displaystyle {\mathcal {B}}} 905: 877:18:53, 24 September 2005 (UTC) 832:18:45, 24 September 2005 (UTC) 551:17:19, 24 September 2005 (UTC) 470:17:14, 24 September 2005 (UTC) 455:17:10, 24 September 2005 (UTC) 1: 5243:06:39, 30 November 2023 (UTC) 4154:{\displaystyle \Pi _{1}^{P}=} 2989:has settled down to boldface 2713:13:32, 18 February 2010 (UTC) 2698:12:53, 18 February 2010 (UTC) 2686:12:49, 18 February 2010 (UTC) 2506:00:13, 18 February 2010 (UTC) 2337:04:03, 23 December 2006 (UTC) 2300:04:09, 8 September 2023 (UTC) 2236:00:05, 26 February 2006 (UTC) 2227:00:43, 25 February 2006 (UTC) 2216:), and mutatis mutandis for Π 2159:22:36, 24 February 2006 (UTC) 2140:22:49, 24 February 2006 (UTC) 2130:22:36, 24 February 2006 (UTC) 1862:and for a suitable numbering 289:and see a list of open tasks. 42:Put new text under old text. 5287:B-Class mathematics articles 4777:{\displaystyle \Pi _{3}^{P}} 4473:{\displaystyle \Pi _{2}^{P}} 4227:{\displaystyle \Sigma _{1}=} 3705:{\displaystyle n\to \infty } 1737:{\displaystyle \mathbb {N} } 1644:{\displaystyle \mathbb {Q} } 1586:{\displaystyle \mathbb {Q} } 1525:{\displaystyle \mathbb {R} } 1503:{\displaystyle \mathbb {Q} } 1474:{\displaystyle \Pi _{1}^{0}} 1406:{\displaystyle \mathbb {R} } 1384:{\displaystyle \mathbb {Q} } 1319:{\displaystyle \mathbb {R} } 1004:on your topological basis. 5208:21:42, 14 August 2023 (UTC) 5192:09:40, 14 August 2023 (UTC) 4844:{\displaystyle \Sigma _{3}} 4709:{\displaystyle \Delta _{2}} 4540:{\displaystyle \Sigma _{2}} 4405:{\displaystyle \Delta _{1}} 4076:{\displaystyle \Delta _{0}} 3853:hierarchies overview/NavBox 3766:has this property as well. 3679:{\displaystyle \pm \infty } 3631:with integer coefficients. 2386:{\displaystyle \Sigma ^{n}} 820:{\displaystyle G_{\delta }} 429:16:12, 1 October 2016 (UTC) 50:New to Knowledge? Welcome! 5308: 4048:{\displaystyle {\Bigg \}}} 3847:21:57, 28 April 2023 (UTC) 3832:06:32, 28 April 2023 (UTC) 2354:20:11, 15 April 2011 (UTC) 5096: 5075: 5054: 5024: 4984: 4947: 4924: 4903: 4882: 4785: 4689: 4578: 4481: 4385: 4268: 4165: 4056: 4031: 3986: 3957: 3918: 3909: 3900: 3891: 3759:{\displaystyle X_{\phi }} 3732:{\displaystyle X_{\psi }} 3473:{\displaystyle X_{\psi }} 3446:{\displaystyle X_{\phi }} 3290:{\displaystyle X_{\phi }} 2786:sets are the same as the 2721:Extensions and variations 2285:11:32, 26 June 2006 (UTC) 2212:(which is a stage of the 2202:formula in the structure 2196:set can be defined by a Σ 1189:-computable sets for any 438:article on the move again 314: 247: 226: 80:Be welcoming to newcomers 5231:Baire space (set theory) 4872:{\displaystyle \Pi _{3}} 4568:{\displaystyle \Pi _{2}} 4258:{\displaystyle \Pi _{1}} 3602:{\displaystyle p(n): --> 3531:{\displaystyle \psi (n)} 3502:{\displaystyle \psi (n)} 3379:for all quantifier-free 3077:20:35, 24 May 2018 (UTC) 2980:20:14, 24 May 2018 (UTC) 2581:{\displaystyle \Pi ^{n}} 2451:{\displaystyle \Pi ^{n}} 1564:, that is, effectively F 321:project's priority scale 5134:{\displaystyle \omega } 5109:{\displaystyle \vdots } 5088:{\displaystyle \vdots } 5067:{\displaystyle \vdots } 4937:{\displaystyle \vdots } 4916:{\displaystyle \vdots } 4895:{\displaystyle \vdots } 3903:(Strong) Exponential H. 3424:disjunctive normal form 3346:, we are claiming that 2985:I think the meaning of 2940:{\displaystyle n\geq 1} 2895:property also hold for 406:14:15 12 Jun 2003 (UTC) 278:WikiProject Mathematics 5257:B-Class vital articles 5170: 5135: 5110: 5089: 5068: 5045: 5016: 4976: 4938: 4917: 4896: 4873: 4845: 4817: 4778: 4745: 4710: 4682: 4643: 4604: 4569: 4541: 4513: 4474: 4441: 4406: 4378: 4336: 4294: 4259: 4228: 4197: 4155: 4116: 4077: 4049: 4021: 3978: 3947: 3816: 3783: 3760: 3733: 3706: 3680: 3657: 3625: 3604: 3567: 3566:{\displaystyle p(n)=0} 3532: 3503: 3474: 3447: 3416: 3393: 3373: 3340: 3291: 3261: 3241: 3168: 3113: 3050: 3015: 2941: 2915: 2889: 2812: 2780: 2748: 2672: 2632: 2582: 2555: 2490: 2452: 2425: 2387: 2123:Relative computability 2027: 1995: 1963: 1943: 1914: 1890: 1856: 1811: 1782: 1762: 1738: 1716: 1645: 1623: 1587: 1558: 1526: 1504: 1475: 1435: 1407: 1385: 1344: 1320: 1298: 1270: 1237: 1213: 1183: 1163: 1127: 1103: 1066: 1034: 998: 978: 946: 919: 862: 821: 794: 764: 729: 697: 653: 617: 585: 536: 504: 368:deleted by other users 75:avoid personal attacks 25:Arithmetical hierarchy 5171: 5136: 5111: 5090: 5069: 5046: 5017: 4977: 4939: 4918: 4897: 4874: 4846: 4818: 4779: 4746: 4711: 4683: 4644: 4605: 4570: 4542: 4514: 4475: 4442: 4407: 4379: 4337: 4295: 4260: 4229: 4198: 4156: 4117: 4078: 4050: 4022: 3979: 3948: 3817: 3784: 3761: 3734: 3707: 3681: 3658: 3626: 3605: 3568: 3533: 3504: 3475: 3448: 3417: 3415:{\displaystyle \phi } 3394: 3392:{\displaystyle \phi } 3374: 3341: 3292: 3262: 3260:{\displaystyle \phi } 3242: 3169: 3114: 3051: 3016: 2942: 2916: 2890: 2813: 2781: 2749: 2673: 2633: 2583: 2556: 2491: 2453: 2426: 2388: 2327:comment was added by 2214:von Neumann hierarchy 2028: 1996: 1964: 1944: 1915: 1891: 1857: 1812: 1783: 1763: 1739: 1717: 1646: 1624: 1588: 1559: 1527: 1505: 1476: 1436: 1408: 1386: 1345: 1321: 1299: 1271: 1238: 1214: 1184: 1164: 1128: 1104: 1067: 1035: 999: 979: 947: 920: 863: 822: 795: 765: 730: 698: 654: 618: 586: 542:set is "effectively F 537: 505: 478:. The idea is that a 205:level-5 vital article 100:Neutral point of view 5145: 5125: 5100: 5079: 5058: 5028: 4988: 4951: 4928: 4907: 4886: 4856: 4828: 4789: 4756: 4723: 4693: 4654: 4615: 4582: 4552: 4524: 4485: 4452: 4419: 4389: 4350: 4305: 4272: 4242: 4208: 4169: 4130: 4091: 4060: 4035: 3990: 3961: 3922: 3793: 3773: 3743: 3716: 3690: 3667: 3656:{\displaystyle p(n)} 3638: 3615: 3611:for some polynomial 3578: 3542: 3513: 3484: 3457: 3430: 3406: 3383: 3350: 3301: 3274: 3251: 3178: 3146: 3091: 3025: 2993: 2925: 2899: 2825: 2790: 2758: 2732: 2642: 2597: 2565: 2527: 2462: 2435: 2397: 2370: 2278:analytical hierarchy 2271:analytical hierarchy 2244:Major edit 2006-6-13 2167:Just in case you're 2152:Analytical hierarchy 2005: 1973: 1953: 1933: 1900: 1866: 1821: 1792: 1772: 1748: 1726: 1676: 1633: 1601: 1575: 1536: 1514: 1492: 1453: 1417: 1413:. For each rational 1395: 1373: 1330: 1308: 1284: 1256: 1223: 1193: 1173: 1169:of naturals) as the 1141: 1113: 1102:{\displaystyle \nu } 1093: 1044: 1012: 997:{\displaystyle \nu } 988: 956: 932: 891: 840: 804: 774: 742: 707: 675: 631: 595: 563: 514: 482: 444:analytical hierarchy 301:mathematics articles 105:No original research 5165: 5011: 4968: 4812: 4773: 4740: 4677: 4638: 4599: 4508: 4469: 4436: 4373: 4328: 4289: 4192: 4147: 4108: 4013: 3939: 3163: 3108: 3045: 3010: 2914:{\displaystyle n=0} 2884: 2860: 2842: 2821:Lastly doesn't the 2807: 2775: 2747:{\displaystyle n=0} 2627: 2550: 2485: 2420: 2222:. Hope this helps, 2022: 1990: 1618: 1553: 1470: 1158: 1061: 1029: 973: 857: 759: 724: 692: 648: 612: 580: 531: 499: 5166: 5148: 5131: 5106: 5085: 5064: 5041: 5012: 4991: 4972: 4954: 4934: 4913: 4892: 4869: 4841: 4813: 4792: 4774: 4759: 4741: 4726: 4706: 4678: 4657: 4639: 4618: 4600: 4585: 4565: 4537: 4509: 4488: 4470: 4455: 4437: 4422: 4402: 4374: 4353: 4332: 4308: 4290: 4275: 4255: 4224: 4193: 4172: 4151: 4133: 4112: 4094: 4073: 4045: 4017: 3993: 3974: 3943: 3925: 3812: 3779: 3756: 3729: 3712:. It follows that 3702: 3676: 3653: 3621: 3599: 3563: 3528: 3499: 3470: 3443: 3412: 3389: 3369: 3336: 3287: 3257: 3237: 3164: 3149: 3142:We claim that the 3109: 3094: 3058:analytic hierarchy 3046: 3028: 3011: 2996: 2937: 2911: 2885: 2864: 2846: 2828: 2808: 2793: 2776: 2761: 2744: 2668: 2628: 2613: 2578: 2551: 2530: 2486: 2465: 2448: 2421: 2400: 2383: 2119:co-A-recursive set 2113:co-A-recursive set 2023: 2008: 1991: 1976: 1959: 1939: 1910: 1896:, the elements of 1886: 1852: 1807: 1778: 1758: 1734: 1712: 1641: 1619: 1604: 1583: 1554: 1539: 1522: 1500: 1471: 1456: 1447:effectively closed 1431: 1403: 1381: 1340: 1316: 1294: 1266: 1233: 1209: 1179: 1159: 1144: 1123: 1099: 1062: 1047: 1030: 1015: 994: 974: 959: 942: 915: 858: 843: 817: 790: 760: 745: 725: 710: 693: 678: 649: 634: 613: 598: 581: 566: 532: 517: 500: 485: 270:Mathematics portal 214:content assessment 86:dispute resolution 47: 5119: 5118: 3972: 3782:{\displaystyle X} 3624:{\displaystyle p} 3270:That is, writing 2978: 2340: 2121:is a redirect to 1962:{\displaystyle B} 1942:{\displaystyle X} 1781:{\displaystyle X} 1510:, as a subset of 1182:{\displaystyle B} 431: 382: 381: 357:in most browsers. 335: 334: 331: 330: 327: 326: 183: 182: 66:Assume good faith 43: 5299: 5175: 5173: 5172: 5167: 5164: 5156: 5140: 5138: 5137: 5132: 5115: 5113: 5112: 5107: 5094: 5092: 5091: 5086: 5073: 5071: 5070: 5065: 5050: 5048: 5047: 5042: 5040: 5039: 5021: 5019: 5018: 5013: 5010: 4999: 4981: 4979: 4978: 4973: 4967: 4962: 4943: 4941: 4940: 4935: 4922: 4920: 4919: 4914: 4901: 4899: 4898: 4893: 4878: 4876: 4875: 4870: 4868: 4867: 4850: 4848: 4847: 4842: 4840: 4839: 4822: 4820: 4819: 4814: 4811: 4800: 4783: 4781: 4780: 4775: 4772: 4767: 4750: 4748: 4747: 4742: 4739: 4734: 4715: 4713: 4712: 4707: 4705: 4704: 4687: 4685: 4684: 4679: 4676: 4665: 4648: 4646: 4645: 4640: 4637: 4626: 4609: 4607: 4606: 4601: 4598: 4593: 4574: 4572: 4571: 4566: 4564: 4563: 4546: 4544: 4543: 4538: 4536: 4535: 4518: 4516: 4515: 4510: 4507: 4496: 4479: 4477: 4476: 4471: 4468: 4463: 4446: 4444: 4443: 4438: 4435: 4430: 4411: 4409: 4408: 4403: 4401: 4400: 4383: 4381: 4380: 4375: 4372: 4361: 4341: 4339: 4338: 4333: 4327: 4316: 4299: 4297: 4296: 4291: 4288: 4283: 4264: 4262: 4261: 4256: 4254: 4253: 4233: 4231: 4230: 4225: 4220: 4219: 4202: 4200: 4199: 4194: 4191: 4180: 4160: 4158: 4157: 4152: 4146: 4141: 4121: 4119: 4118: 4113: 4107: 4102: 4082: 4080: 4079: 4074: 4072: 4071: 4054: 4052: 4051: 4046: 4044: 4043: 4026: 4024: 4023: 4018: 4012: 4001: 3983: 3981: 3980: 3975: 3973: 3965: 3952: 3950: 3949: 3944: 3938: 3933: 3914: 3905: 3896: 3889: 3888: 3883: 3876: 3869: 3863: 3821: 3819: 3818: 3813: 3805: 3804: 3788: 3786: 3785: 3780: 3765: 3763: 3762: 3757: 3755: 3754: 3738: 3736: 3735: 3730: 3728: 3727: 3711: 3709: 3708: 3703: 3685: 3683: 3682: 3677: 3662: 3660: 3659: 3654: 3630: 3628: 3627: 3622: 3610: 3607: 3606: 3600: 3572: 3570: 3569: 3564: 3537: 3535: 3534: 3529: 3508: 3506: 3505: 3500: 3479: 3477: 3476: 3471: 3469: 3468: 3452: 3450: 3449: 3444: 3442: 3441: 3421: 3419: 3418: 3413: 3398: 3396: 3395: 3390: 3378: 3376: 3375: 3370: 3368: 3367: 3345: 3343: 3342: 3337: 3317: 3296: 3294: 3293: 3288: 3286: 3285: 3266: 3264: 3263: 3258: 3246: 3244: 3243: 3238: 3200: 3173: 3171: 3170: 3165: 3162: 3157: 3118: 3116: 3115: 3110: 3107: 3102: 3055: 3053: 3052: 3047: 3044: 3039: 3020: 3018: 3017: 3012: 3009: 3004: 2968: 2946: 2944: 2943: 2938: 2920: 2918: 2917: 2912: 2894: 2892: 2891: 2886: 2883: 2878: 2859: 2854: 2841: 2836: 2817: 2815: 2814: 2809: 2806: 2801: 2785: 2783: 2782: 2777: 2774: 2769: 2753: 2751: 2750: 2745: 2677: 2675: 2674: 2669: 2667: 2666: 2654: 2653: 2637: 2635: 2634: 2629: 2626: 2621: 2609: 2608: 2587: 2585: 2584: 2579: 2577: 2576: 2560: 2558: 2557: 2552: 2549: 2544: 2495: 2493: 2492: 2487: 2484: 2479: 2457: 2455: 2454: 2449: 2447: 2446: 2430: 2428: 2427: 2422: 2419: 2414: 2392: 2390: 2389: 2384: 2382: 2381: 2322: 2321:Thanks, Andy D. 2177:, the subscript 2137:Charles Matthews 2032: 2030: 2029: 2024: 2021: 2016: 2000: 1998: 1997: 1992: 1989: 1984: 1968: 1966: 1965: 1960: 1948: 1946: 1945: 1940: 1919: 1917: 1916: 1911: 1909: 1908: 1895: 1893: 1892: 1887: 1879: 1861: 1859: 1858: 1853: 1839: 1838: 1816: 1814: 1813: 1808: 1806: 1805: 1804: 1787: 1785: 1784: 1779: 1767: 1765: 1764: 1759: 1757: 1756: 1743: 1741: 1740: 1735: 1733: 1721: 1719: 1718: 1713: 1711: 1710: 1709: 1696: 1695: 1694: 1650: 1648: 1647: 1642: 1640: 1628: 1626: 1625: 1620: 1617: 1612: 1592: 1590: 1589: 1584: 1582: 1563: 1561: 1560: 1555: 1552: 1547: 1531: 1529: 1528: 1523: 1521: 1509: 1507: 1506: 1501: 1499: 1480: 1478: 1477: 1472: 1469: 1464: 1440: 1438: 1437: 1432: 1430: 1412: 1410: 1409: 1404: 1402: 1390: 1388: 1387: 1382: 1380: 1349: 1347: 1346: 1341: 1339: 1338: 1325: 1323: 1322: 1317: 1315: 1303: 1301: 1300: 1295: 1293: 1292: 1275: 1273: 1272: 1267: 1265: 1264: 1242: 1240: 1239: 1234: 1232: 1231: 1218: 1216: 1215: 1210: 1208: 1207: 1188: 1186: 1185: 1180: 1168: 1166: 1165: 1160: 1157: 1152: 1132: 1130: 1129: 1124: 1122: 1121: 1108: 1106: 1105: 1100: 1076:set of reals. -- 1071: 1069: 1068: 1063: 1060: 1055: 1039: 1037: 1036: 1031: 1028: 1023: 1003: 1001: 1000: 995: 983: 981: 980: 975: 972: 967: 951: 949: 948: 943: 941: 940: 924: 922: 921: 916: 914: 913: 904: 867: 865: 864: 859: 856: 851: 826: 824: 823: 818: 816: 815: 799: 797: 796: 791: 789: 788: 769: 767: 766: 761: 758: 753: 734: 732: 731: 726: 723: 718: 702: 700: 699: 694: 691: 686: 658: 656: 655: 650: 647: 642: 622: 620: 619: 614: 611: 606: 590: 588: 587: 582: 579: 574: 546:", and so on. -- 541: 539: 538: 533: 530: 525: 509: 507: 506: 501: 498: 493: 376:Reporting errors 344: 343: 337: 303: 302: 299: 296: 293: 272: 267: 266: 256: 249: 248: 243: 235: 228: 211: 202: 201: 194: 193: 185: 179: 178: 164: 95:Article policies 16: 5307: 5306: 5302: 5301: 5300: 5298: 5297: 5296: 5247: 5246: 5216: 5184:CaffeineWitcher 5143: 5142: 5123: 5122: 5098: 5097: 5077: 5076: 5056: 5055: 5031: 5026: 5025: 4986: 4985: 4949: 4948: 4926: 4925: 4905: 4904: 4884: 4883: 4859: 4854: 4853: 4831: 4826: 4825: 4787: 4786: 4754: 4753: 4721: 4720: 4696: 4691: 4690: 4652: 4651: 4613: 4612: 4580: 4579: 4555: 4550: 4549: 4527: 4522: 4521: 4483: 4482: 4450: 4449: 4417: 4416: 4392: 4387: 4386: 4348: 4347: 4303: 4302: 4270: 4269: 4245: 4240: 4239: 4211: 4206: 4205: 4167: 4166: 4128: 4127: 4089: 4088: 4063: 4058: 4057: 4033: 4032: 3988: 3987: 3959: 3958: 3920: 3919: 3912:Arithmetical H. 3910: 3901: 3892: 3887: 3861: 3855: 3796: 3791: 3790: 3771: 3770: 3746: 3741: 3740: 3719: 3714: 3713: 3688: 3687: 3665: 3664: 3636: 3635: 3613: 3612: 3575: 3574: 3540: 3539: 3511: 3510: 3509:atomic. Such a 3482: 3481: 3460: 3455: 3454: 3433: 3428: 3427: 3426:, we have that 3404: 3403: 3381: 3380: 3359: 3348: 3347: 3299: 3298: 3277: 3272: 3271: 3249: 3248: 3176: 3175: 3144: 3143: 3136: 3089: 3088: 3085: 3023: 3022: 2991: 2990: 2964: 2923: 2922: 2897: 2896: 2823: 2822: 2788: 2787: 2756: 2755: 2730: 2729: 2723: 2658: 2645: 2640: 2639: 2600: 2595: 2594: 2568: 2563: 2562: 2525: 2524: 2460: 2459: 2438: 2433: 2432: 2395: 2394: 2373: 2368: 2367: 2361: 2359:logic hierarchy 2346:129.206.103.183 2341: 2323:—The preceding 2308: 2306:Content Request 2274: 2246: 2221: 2211: 2201: 2195: 2176: 2148: 2115: 2003: 2002: 1971: 1970: 1951: 1950: 1931: 1930: 1898: 1897: 1864: 1863: 1819: 1818: 1795: 1790: 1789: 1770: 1769: 1746: 1745: 1724: 1723: 1700: 1685: 1674: 1673: 1651:is not open. -- 1631: 1630: 1599: 1598: 1597:the union of a 1573: 1572: 1567: 1534: 1533: 1512: 1511: 1490: 1489: 1451: 1450: 1415: 1414: 1393: 1392: 1371: 1370: 1328: 1327: 1306: 1305: 1282: 1281: 1254: 1253: 1221: 1220: 1191: 1190: 1171: 1170: 1139: 1138: 1136: 1111: 1110: 1091: 1090: 1042: 1041: 1010: 1009: 986: 985: 954: 953: 930: 929: 889: 888: 838: 837: 807: 802: 801: 777: 772: 771: 740: 739: 705: 704: 673: 672: 629: 628: 593: 592: 561: 560: 545: 512: 511: 480: 479: 440: 387: 378: 360: 359: 358: 341: 300: 297: 294: 291: 290: 268: 261: 241: 212:on Knowledge's 209: 199: 121: 116: 115: 114: 91: 61: 12: 11: 5: 5305: 5303: 5295: 5294: 5289: 5284: 5279: 5274: 5269: 5264: 5259: 5249: 5248: 5215: 5212: 5211: 5210: 5200:Caleb Stanford 5163: 5160: 5155: 5151: 5130: 5117: 5116: 5105: 5095: 5084: 5074: 5063: 5052: 5051: 5038: 5034: 5023: 5009: 5006: 5003: 4998: 4994: 4983: 4971: 4966: 4961: 4957: 4945: 4944: 4933: 4923: 4912: 4902: 4891: 4880: 4879: 4866: 4862: 4851: 4838: 4834: 4823: 4810: 4807: 4804: 4799: 4795: 4784: 4771: 4766: 4762: 4751: 4738: 4733: 4729: 4717: 4716: 4703: 4699: 4688: 4675: 4672: 4669: 4664: 4660: 4649: 4636: 4633: 4630: 4625: 4621: 4610: 4597: 4592: 4588: 4576: 4575: 4562: 4558: 4547: 4534: 4530: 4519: 4506: 4503: 4500: 4495: 4491: 4480: 4467: 4462: 4458: 4447: 4434: 4429: 4425: 4413: 4412: 4399: 4395: 4384: 4371: 4368: 4365: 4360: 4356: 4345: 4331: 4326: 4323: 4320: 4315: 4311: 4300: 4287: 4282: 4278: 4266: 4265: 4252: 4248: 4237: 4223: 4218: 4214: 4203: 4190: 4187: 4184: 4179: 4175: 4164: 4150: 4145: 4140: 4136: 4125: 4111: 4106: 4101: 4097: 4085: 4084: 4070: 4066: 4055: 4042: 4030: 4016: 4011: 4008: 4005: 4000: 3996: 3985: 3971: 3968: 3956: 3942: 3937: 3932: 3928: 3916: 3915: 3908: 3906: 3899: 3897: 3886: 3885: 3878: 3871: 3860: 3854: 3851: 3850: 3849: 3839:Caleb Stanford 3822:, as claimed. 3811: 3808: 3803: 3799: 3778: 3753: 3749: 3726: 3722: 3701: 3698: 3695: 3675: 3672: 3652: 3649: 3646: 3643: 3620: 3598: 3595: 3592: 3589: 3586: 3583: 3562: 3559: 3556: 3553: 3550: 3547: 3527: 3524: 3521: 3518: 3498: 3495: 3492: 3489: 3467: 3463: 3440: 3436: 3411: 3388: 3366: 3362: 3358: 3355: 3335: 3332: 3329: 3326: 3323: 3320: 3316: 3312: 3309: 3306: 3284: 3280: 3256: 3236: 3233: 3230: 3227: 3224: 3221: 3218: 3215: 3212: 3209: 3206: 3203: 3199: 3195: 3192: 3189: 3186: 3183: 3161: 3156: 3152: 3135: 3132: 3106: 3101: 3097: 3084: 3081: 3080: 3079: 3061: 3043: 3038: 3035: 3031: 3008: 3003: 2999: 2963: 2960: 2936: 2933: 2930: 2910: 2907: 2904: 2882: 2877: 2874: 2871: 2867: 2863: 2858: 2853: 2849: 2845: 2840: 2835: 2831: 2805: 2800: 2796: 2773: 2768: 2764: 2743: 2740: 2737: 2722: 2719: 2718: 2717: 2716: 2715: 2688: 2665: 2661: 2657: 2652: 2648: 2625: 2620: 2616: 2612: 2607: 2603: 2575: 2571: 2548: 2543: 2540: 2537: 2533: 2513:Same as before 2483: 2478: 2475: 2472: 2468: 2445: 2441: 2418: 2413: 2410: 2407: 2403: 2380: 2376: 2360: 2357: 2320: 2307: 2304: 2303: 2302: 2273: 2267: 2263: 2262: 2259: 2256: 2253: 2245: 2242: 2241: 2240: 2239: 2238: 2217: 2206: 2197: 2191: 2185:tells you the 2172: 2165: 2147: 2144: 2143: 2142: 2114: 2111: 2104: 2103: 2102: 2101: 2100: 2099: 2098: 2097: 2096: 2095: 2094: 2093: 2092: 2091: 2053: 2052: 2051: 2050: 2049: 2048: 2047: 2046: 2045: 2044: 2020: 2015: 2011: 1988: 1983: 1979: 1958: 1938: 1907: 1885: 1882: 1878: 1874: 1871: 1851: 1848: 1845: 1842: 1837: 1832: 1829: 1826: 1803: 1798: 1777: 1755: 1732: 1708: 1703: 1699: 1693: 1688: 1684: 1681: 1663: 1662: 1661: 1660: 1659: 1658: 1639: 1616: 1611: 1607: 1581: 1569: 1565: 1551: 1546: 1542: 1520: 1498: 1486: 1468: 1463: 1459: 1449:set, that is, 1429: 1425: 1422: 1401: 1379: 1362: 1361: 1360: 1359: 1358: 1357: 1337: 1314: 1291: 1263: 1230: 1206: 1201: 1198: 1178: 1156: 1151: 1147: 1134: 1120: 1098: 1084: 1083: 1059: 1054: 1050: 1027: 1022: 1018: 993: 971: 966: 962: 939: 926: 925: 912: 907: 903: 899: 896: 882: 881: 880: 879: 855: 850: 846: 814: 810: 787: 784: 780: 757: 752: 748: 736: 722: 717: 713: 690: 685: 681: 646: 641: 637: 610: 605: 601: 578: 573: 569: 556: 555: 554: 553: 543: 529: 524: 520: 497: 492: 488: 439: 436: 435: 434: 433: 432: 427:comment added 408: 407: 398: 397: 394: 386: 383: 380: 379: 373: 372: 371: 355:case-sensitive 349: 348: 347: 345: 333: 332: 329: 328: 325: 324: 313: 307: 306: 304: 287:the discussion 274: 273: 257: 245: 244: 236: 224: 223: 217: 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: 5304: 5293: 5290: 5288: 5285: 5283: 5280: 5278: 5275: 5273: 5270: 5268: 5265: 5263: 5260: 5258: 5255: 5254: 5252: 5245: 5244: 5240: 5236: 5232: 5227: 5225: 5221: 5213: 5209: 5205: 5201: 5196: 5195: 5194: 5193: 5189: 5185: 5181: 5179: 5161: 5158: 5153: 5149: 5128: 5103: 5082: 5061: 5053: 5036: 5007: 5004: 5001: 4996: 4969: 4964: 4959: 4946: 4931: 4910: 4889: 4881: 4864: 4852: 4836: 4824: 4808: 4805: 4802: 4797: 4769: 4764: 4752: 4736: 4731: 4719: 4718: 4701: 4673: 4670: 4667: 4662: 4650: 4634: 4631: 4628: 4623: 4611: 4595: 4590: 4577: 4560: 4548: 4532: 4520: 4504: 4501: 4498: 4493: 4465: 4460: 4448: 4432: 4427: 4415: 4414: 4397: 4369: 4366: 4363: 4358: 4346: 4344: 4329: 4324: 4321: 4318: 4313: 4301: 4285: 4280: 4267: 4250: 4238: 4236: 4221: 4216: 4204: 4188: 4185: 4182: 4177: 4163: 4148: 4143: 4138: 4126: 4124: 4109: 4104: 4099: 4087: 4086: 4068: 4029: 4014: 4009: 4006: 4003: 3998: 3969: 3966: 3955: 3940: 3935: 3930: 3917: 3913: 3907: 3904: 3898: 3895: 3894:Polynomial H. 3890: 3884: 3879: 3877: 3872: 3870: 3865: 3864: 3859: 3852: 3848: 3844: 3840: 3836: 3835: 3834: 3833: 3829: 3825: 3809: 3806: 3801: 3797: 3776: 3767: 3751: 3747: 3724: 3720: 3693: 3670: 3647: 3641: 3632: 3618: 3596: 3593: 3587: 3581: 3560: 3557: 3551: 3545: 3522: 3516: 3493: 3487: 3465: 3461: 3438: 3434: 3425: 3409: 3400: 3386: 3364: 3360: 3356: 3353: 3327: 3321: 3318: 3310: 3307: 3282: 3278: 3268: 3254: 3228: 3225: 3222: 3219: 3213: 3210: 3207: 3201: 3193: 3190: 3184: 3181: 3159: 3154: 3140: 3133: 3131: 3130: 3126: 3122: 3104: 3099: 3083:Pronunciation 3082: 3078: 3074: 3070: 3066: 3062: 3059: 3041: 3036: 3033: 3006: 3001: 2988: 2984: 2983: 2982: 2981: 2976: 2972: 2961: 2959: 2958: 2954: 2950: 2934: 2931: 2928: 2908: 2905: 2902: 2880: 2875: 2872: 2869: 2861: 2856: 2851: 2843: 2838: 2833: 2819: 2803: 2798: 2771: 2766: 2741: 2738: 2735: 2726: 2720: 2714: 2710: 2706: 2705:66.127.55.192 2701: 2700: 2699: 2696: 2693: 2689: 2687: 2684: 2681: 2663: 2655: 2650: 2623: 2618: 2610: 2605: 2591: 2573: 2546: 2541: 2538: 2535: 2522: 2518: 2514: 2510: 2509: 2508: 2507: 2503: 2499: 2498:66.127.55.192 2481: 2476: 2473: 2470: 2443: 2416: 2411: 2408: 2405: 2378: 2365: 2358: 2356: 2355: 2351: 2347: 2338: 2334: 2330: 2329:66.117.149.88 2326: 2319: 2315: 2311: 2305: 2301: 2297: 2293: 2292:76.254.27.203 2289: 2288: 2287: 2286: 2283: 2279: 2272: 2268: 2266: 2260: 2257: 2254: 2251: 2250: 2249: 2243: 2237: 2234: 2230: 2229: 2228: 2225: 2220: 2215: 2210: 2205: 2200: 2194: 2188: 2184: 2180: 2175: 2170: 2166: 2163: 2162: 2161: 2160: 2157: 2153: 2146:superscript 0 2145: 2141: 2138: 2134: 2133: 2132: 2131: 2128: 2124: 2120: 2112: 2110: 2109: 2090: 2087: 2083: 2079: 2075: 2074: 2073: 2070: 2065: 2064: 2063: 2062: 2061: 2060: 2059: 2058: 2057: 2056: 2055: 2054: 2043: 2040: 2036: 2018: 2013: 1986: 1981: 1956: 1936: 1928: 1927: 1926: 1923: 1883: 1872: 1869: 1849: 1846: 1843: 1840: 1830: 1827: 1796: 1775: 1701: 1686: 1682: 1679: 1671: 1670: 1669: 1668: 1667: 1666: 1665: 1664: 1657: 1654: 1614: 1609: 1596: 1570: 1549: 1544: 1487: 1484: 1466: 1461: 1448: 1444: 1423: 1420: 1368: 1367: 1366: 1365: 1364: 1363: 1356: 1353: 1279: 1251: 1250: 1249: 1246: 1199: 1196: 1176: 1154: 1149: 1096: 1088: 1087: 1086: 1085: 1082: 1079: 1075: 1057: 1052: 1025: 1020: 1007: 1006: 1005: 991: 969: 964: 897: 894: 887: 886: 885: 878: 875: 871: 853: 848: 835: 834: 833: 830: 812: 808: 785: 782: 778: 755: 750: 737: 720: 715: 688: 683: 670: 666: 662: 644: 639: 626: 625: 624: 608: 603: 576: 571: 552: 549: 527: 522: 495: 490: 477: 473: 472: 471: 468: 464: 459: 458: 457: 456: 453: 449: 445: 437: 430: 426: 420: 416: 412: 411: 410: 409: 405: 400: 399: 395: 392: 391: 390: 384: 377: 369: 365: 364: 363: 356: 352: 346: 339: 338: 322: 318: 312: 309: 308: 305: 288: 284: 280: 279: 271: 265: 260: 258: 255: 251: 250: 246: 240: 237: 234: 230: 225: 221: 215: 207: 206: 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: 5228: 5224:Cantor space 5217: 5182: 5120: 3856: 3768: 3633: 3401: 3269: 3141: 3137: 3086: 3064: 3057: 2986: 2965: 2820: 2727: 2724: 2589: 2561:-formula is 2521:second-order 2520: 2516: 2512: 2362: 2342: 2316: 2312: 2309: 2275: 2264: 2247: 2218: 2208: 2203: 2198: 2192: 2186: 2182: 2178: 2173: 2168: 2149: 2117:The link to 2116: 2105: 2081: 2077: 2034: 1594: 1482: 1446: 1442: 1277: 1073: 927: 883: 869: 669:Cantor space 557: 447: 441: 388: 361: 353:Anchors are 350: 317:Mid-priority 316: 276: 242:Mid‑priority 220:WikiProjects 203: 171: 165: 157: 150: 144: 138: 132: 122: 94: 19:This is the 5220:Baire space 5214:Baire Space 3862:This box: 3402:By putting 703:, but with 665:Baire space 661:clopen sets 423:—Preceding 292:Mathematics 283:mathematics 239:Mathematics 148:free images 31:not a forum 5251:Categories 3609:0}" /: --> 3065:analytical 2108:MathMartin 2069:MathMartin 1922:MathMartin 1245:MathMartin 467:MathMartin 415:91.66.2.94 3069:Trovatore 2224:Trovatore 2086:Trovatore 2039:Trovatore 1653:Trovatore 1352:Trovatore 1326:, not of 1078:Trovatore 874:Trovatore 829:Trovatore 548:Trovatore 452:Trovatore 208:is rated 88:if needed 71:Be polite 21:talk page 3577:0}": --> 2987:analytic 2949:Catrincm 2325:unsigned 2282:CMummert 2233:Bcrowell 2156:Bcrowell 2127:Bcrowell 1817:so that 1488:The set 1445:} is an 1089:Ok, but 623:sets ? 385:Untitled 56:get help 29:This is 27:article. 5235:Jrvarma 4028:EXPTIME 3984:PSPACE 3858:this: 3634:Such a 3139:ones): 2082:section 2078:article 2035:problem 1278:subsets 425:undated 370:before. 319:on the 210:B-class 154:WP refs 142:scholar 5022:=EXPH 3573:or to 2818:ones. 2458:means 2169:asking 928:where 827:'s. -- 216:scale. 126:Google 3824:Jslam 3594:: --> 3480:with 2592:: --> 1532:, is 476:bases 197:This 169:JSTOR 130:books 84:Seek 5239:talk 5204:talk 5188:talk 5178:here 4343:NEXP 4235:c.e. 4162:CoNP 3882:edit 3875:talk 3868:view 3843:talk 3828:talk 3769:But 3297:for 3174:set 3125:talk 3121:N4m3 3073:talk 3034:< 2975:talk 2953:talk 2709:talk 2692:Emil 2680:Emil 2588:for 2502:talk 2350:talk 2333:talk 2296:talk 2269:See 2187:type 1571:But 1350:. -- 1074:open 870:cube 738:The 627:The 448:what 419:talk 351:Tip: 162:FENS 136:news 73:and 5222:or 5141:or 4982:PH 3686:as 3422:in 2971:CBM 2962:-al 1788:of 1595:not 1593:is 1441:, { 1280:of 667:or 421:) 404:Pde 311:Mid 176:TWL 5253:: 5241:) 5206:) 5190:) 5180:) 5150:ω 5129:ω 5104:⋮ 5083:⋮ 5062:⋮ 5037:ω 5033:Δ 4997:ω 4993:Δ 4960:ω 4956:Δ 4932:⋮ 4911:⋮ 4890:⋮ 4861:Π 4833:Σ 4794:Δ 4761:Π 4728:Σ 4698:Δ 4659:Π 4620:Σ 4587:Δ 4557:Π 4529:Σ 4490:Δ 4457:Π 4424:Σ 4394:Δ 4355:Π 4310:Σ 4277:Δ 4247:Π 4213:Σ 4174:Δ 4135:Π 4123:NP 4096:Σ 4083:= 4065:Δ 3995:Δ 3967:⊆ 3927:Δ 3845:) 3830:) 3807:≠ 3802:ϕ 3752:ϕ 3725:ψ 3700:∞ 3697:→ 3674:∞ 3671:± 3603:0} 3517:ψ 3488:ψ 3466:ψ 3439:ϕ 3410:ϕ 3399:. 3387:ϕ 3365:ϕ 3357:≠ 3322:ϕ 3319:∣ 3311:∈ 3283:ϕ 3267:. 3255:ϕ 3211:≤ 3205:∃ 3202:∣ 3194:∈ 3151:Δ 3127:) 3096:Σ 3075:) 3037:ω 3030:Σ 2998:Σ 2973:· 2955:) 2947:. 2932:≥ 2866:Δ 2862:⊊ 2848:Π 2844:∪ 2830:Σ 2795:Δ 2763:Δ 2711:) 2695:J. 2683:J. 2678:.— 2660:Σ 2656:∩ 2647:Π 2615:Σ 2602:Π 2570:Π 2539:− 2532:Π 2515:, 2504:) 2474:− 2467:Σ 2440:Π 2409:− 2402:Π 2375:Σ 2352:) 2335:) 2298:) 2207:ω+ 2010:Σ 1978:Σ 1881:→ 1870:ν 1847:∈ 1831:∈ 1825:∀ 1698:→ 1606:Σ 1541:Σ 1458:Π 1424:∈ 1200:∈ 1146:Σ 1097:ν 1049:Σ 1017:Σ 992:ν 961:Σ 906:→ 895:ν 845:Σ 813:δ 786:σ 783:δ 747:Σ 712:Σ 680:Σ 636:Σ 600:Σ 568:Σ 519:Σ 487:Σ 156:) 54:; 5237:( 5202:( 5186:( 5162:K 5159:C 5154:1 5008:P 5005:X 5002:E 4970:= 4965:P 4865:3 4837:3 4809:P 4806:X 4803:E 4798:3 4770:P 4765:3 4737:P 4732:3 4702:2 4674:P 4671:X 4668:E 4663:2 4635:P 4632:X 4629:E 4624:2 4596:P 4591:2 4561:2 4533:2 4505:P 4502:X 4499:E 4494:2 4466:P 4461:2 4433:P 4428:2 4398:1 4370:P 4367:X 4364:E 4359:1 4330:= 4325:P 4322:X 4319:E 4314:1 4286:P 4281:1 4251:1 4222:= 4217:1 4189:P 4186:X 4183:E 4178:1 4149:= 4144:P 4139:1 4110:= 4105:P 4100:1 4069:0 4041:} 4015:= 4010:P 4007:X 4004:E 3999:0 3970:? 3954:P 3941:= 3936:P 3931:0 3841:( 3826:( 3810:X 3798:X 3777:X 3748:X 3721:X 3694:n 3651:) 3648:n 3645:( 3642:p 3619:p 3597:0 3591:) 3588:n 3585:( 3582:p 3561:0 3558:= 3555:) 3552:n 3549:( 3546:p 3526:) 3523:n 3520:( 3497:) 3494:n 3491:( 3462:X 3435:X 3361:X 3354:X 3334:} 3331:) 3328:n 3325:( 3315:N 3308:n 3305:{ 3279:X 3235:} 3232:) 3229:n 3226:= 3223:k 3220:2 3217:( 3214:n 3208:k 3198:N 3191:n 3188:{ 3185:= 3182:X 3160:0 3155:0 3123:( 3105:0 3100:1 3071:( 3042:1 3007:1 3002:1 2977:) 2969:( 2951:( 2935:1 2929:n 2909:0 2906:= 2903:n 2881:0 2876:1 2873:+ 2870:n 2857:0 2852:n 2839:0 2834:n 2804:0 2799:1 2772:0 2767:0 2742:0 2739:= 2736:n 2707:( 2664:2 2651:2 2624:0 2619:1 2611:= 2606:1 2590:n 2574:n 2547:1 2542:1 2536:n 2500:( 2482:0 2477:1 2471:n 2444:n 2417:0 2412:1 2406:n 2379:n 2348:( 2339:. 2331:( 2294:( 2219:m 2209:n 2204:V 2199:m 2193:m 2190:Σ 2183:n 2179:m 2174:m 2019:0 2014:n 1987:0 1982:n 1957:B 1937:X 1906:B 1884:X 1877:N 1873:: 1850:X 1844:B 1841:: 1836:B 1828:B 1802:R 1797:2 1776:X 1754:B 1731:N 1707:R 1702:2 1692:N 1687:2 1683:: 1680:f 1638:Q 1615:0 1610:2 1580:Q 1566:σ 1550:0 1545:2 1519:R 1497:Q 1483:q 1467:0 1462:1 1443:q 1428:Q 1421:q 1400:R 1378:Q 1336:B 1313:R 1290:B 1262:B 1229:B 1205:B 1197:B 1177:B 1155:0 1150:2 1135:σ 1119:B 1058:0 1053:2 1026:0 1021:1 970:0 965:1 938:B 911:B 902:N 898:: 854:0 849:1 809:G 779:G 756:0 751:3 735:. 721:0 716:1 689:0 684:0 645:0 640:0 609:0 604:3 577:0 572:0 544:σ 528:0 523:2 496:0 491:1 417:( 323:. 222:: 172:· 166:· 158:· 151:· 145:· 139:· 133:· 128:( 58:.

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