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Apr 7, 2020 at 7:24 history edited YCor CC BY-SA 4.0
changed tags, changed title, formatted links
Jan 24, 2015 at 14:47 vote accept CommunityBot
Jan 15, 2015 at 13:34 vote accept CommunityBot
Jan 15, 2015 at 13:34
Jan 15, 2015 at 5:24 answer added Bjørn Kjos-Hanssen timeline score: 8
Jan 15, 2015 at 3:01 answer added Joel David Hamkins timeline score: 7
Jan 15, 2015 at 1:55 history reopened user60665
Joel David Hamkins
Stefan Kohl
Bjørn Kjos-Hanssen
Benjamin Steinberg
Jan 14, 2015 at 20:16 comment added Joel David Hamkins The MRDP theorem shows that the c.e. sets are precisely the projections of the zero sets of multivariable polynomials over the integers. Is that the kind of thing that is wanted?
Jan 14, 2015 at 20:10 review Reopen votes
Jan 15, 2015 at 2:00
Jan 14, 2015 at 19:50 history edited user60665 CC BY-SA 3.0
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Jan 14, 2015 at 19:47 history closed Qiaochu Yuan
Noah Schweber
Neil Strickland
Will Jagy
Andrés E. Caicedo
Needs details or clarity
Jan 14, 2015 at 19:45 review Close votes
Jan 14, 2015 at 19:50
Jan 14, 2015 at 19:37 comment added Benjamin Steinberg Presumably he means that regular languages are recognized by finite monoids and context-free languages are recognized by a product of a free group and a finite monoid and so what recognizes an arbitrary recursively enumerable language.
Jan 14, 2015 at 19:36 history edited user60665 CC BY-SA 3.0
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Jan 14, 2015 at 19:30 comment added Noah Schweber I think this question is potentially very interesting, but needs a lot of clarification: for one thing, what do you mean by "an algebraic structure?" For now I've voted to close as "unclear," but I'll happily retract that if the question is improved. OP, if you google around you'll quickly find many things of interest - for example, check out the lamplighter group, or papers such as sciencedirect.com/science/article/pii/S0304397508002326.
Jan 14, 2015 at 19:25 history asked user60665 CC BY-SA 3.0