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HJRW
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Top posts
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answer
47
Most interesting mathematics mistake?
Dec 15, 2009
answer
43
What are some of the big open problems in 3-manifold theory?
Aug 22, 2010
answer
39
finite generated group realized as fundamental group of manifolds
Feb 16, 2010
answer
37
What are your favorite instructional counterexamples?
Mar 2, 2010
question
33
Can a connected planar compactum minus a point be totally disconnected?
Feb 27, 2010
answer
29
Can a group be a universal Turing machine?
Feb 14, 2012
answer
27
Does injectivity of $\pi_1(\partial U) \to \pi_1(M)$ imply injectivity of $\pi_1(U) \to \pi_1(M)$?
Oct 18, 2019
answer
27
Mapping from a finite index subgroup onto the whole group
Mar 2, 2012
answer
25
Primes occurring as orders of elements of a finitely presented group
Feb 8, 2013
answer
25
Fundamental group of 3-manifold with boundary
Nov 19, 2009
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$|G|>2$ implies $G$ has non trivial automorphism
43
subgroups of finitely generated groups with a finite index
30
Finding subgroups of a free group with a specific index
15
A space of ideals
9
Epimorphism from GL(2,Z) to GL(2,Z)