HenrikRüping

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Are the rationals homeomorphic to any power of the rationals?

gn.general-topology asked May 26 '10 at 12:22

mathoverflow.net

25 votes

Which spaces are inverse limits of discrete spaces ?

gn.general-topology asked Feb 16 '10 at 10:34

mathoverflow.net

25 votes

Collatz conjecture for numbers of th form $2^n +1$

co.combinatorics asked Jan 4 '11 at 14:39

mathoverflow.net

22 votes

Accumulation points of uncountable sets

real-analysis general-topology asked Feb 21 '13 at 12:07

math.stackexchange.com

21 votes

Tetrahedra with prescribed face angles

mg.metric-geometry hyperbolic-geometry 3-manifolds euclidean-geometry spherical-geometry asked Feb 24 '10 at 7:54

mathoverflow.net

20 votes

A game played on a rectangle

game-theory asked Nov 22 '12 at 15:07

math.stackexchange.com

18 votes

When is a extension of $\mathbb{Z}$ by a free group a CAT(0) group?

gt.geometric-topology geometric-group-theory alexandrov-geometry asked Feb 1 '11 at 11:11

mathoverflow.net

16 votes

infinite dimensional CAT(0) groups

gr.group-theory mg.metric-geometry dimension-theory alexandrov-geometry asked Jan 5 '12 at 13:23

mathoverflow.net

16 votes

Outer automorphisms of finite extensions

gr.group-theory asked Apr 15 '11 at 12:48

mathoverflow.net

15 votes

Automorphisms of $SL_n(\mathbb{Z})$

gr.group-theory asked Mar 3 '11 at 10:11

mathoverflow.net

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HenrikRüping

Are the rationals homeomorphic to any power of the rationals?

Which spaces are inverse limits of discrete spaces ?

Collatz conjecture for numbers of th form $2^n +1$

Accumulation points of uncountable sets

Tetrahedra with prescribed face angles

A game played on a rectangle

When is a extension of $\mathbb{Z}$ by a free group a CAT(0) group?

infinite dimensional CAT(0) groups

Outer automorphisms of finite extensions

Automorphisms of $SL_n(\mathbb{Z})$