User Arturo Magidin

68 votes

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Measures of non-abelian-ness

answered Mar 25, 2013 at 0:46

65 votes

Extremely messy proofs

answered Oct 27, 2010 at 16:41

54 votes

Proof synopsis collection

answered Oct 30, 2010 at 18:44

33 votes

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Commutator subgroup does not consist only of commutators?

answered Oct 30, 2010 at 20:15

28 votes

Groups for which the $n$-power map is a homomorphism

answered Oct 24, 2017 at 6:58

20 votes

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Non-abelian Grothendieck group

answered Jan 7, 2015 at 20:24

18 votes

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Free division rings?

answered Apr 25, 2010 at 0:33

17 votes

Where is number theory used in the rest of mathematics?

answered Mar 9, 2012 at 16:09

17 votes

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The direct sum of injective modules need not be injective

answered Jul 28, 2012 at 20:46

16 votes

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Do these conditions on a semigroup define a group?

answered Jun 10, 2010 at 18:32

16 votes

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Is there a structure theorem or group law for finite groups generated by two elements?

answered Jul 27, 2015 at 18:27

14 votes

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Center of p-groups

answered Sep 14, 2012 at 19:57

14 votes

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Nielsen-Schreier theorem for monoids

answered Dec 7, 2017 at 20:19

13 votes

Two abelian groups, each being direct factor of the other

answered May 16, 2017 at 19:01

12 votes

Greatest power of two dividing an integer

answered Jun 28, 2010 at 20:31

11 votes

Making N (set of all positive integers) a group

answered May 23, 2010 at 1:14

11 votes

Favorite popular math book

answered Dec 9, 2010 at 4:38

10 votes

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Are the positive multiplicative group and the additive group of the field of real algebraic numbers isomorphic?

answered Apr 11, 2016 at 18:14

10 votes

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Where was it first stated that there are no 4-transitive finite groups other than symmetric, alternating and Mathieu groups?

answered Jul 7, 2013 at 18:42

10 votes

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How many "steps" does one need to obtain a group from a semigroup

answered May 10, 2018 at 4:55

10 votes

Mathematical Writing: Proof Outlines/Overview in a Paper

answered Aug 13, 2018 at 18:04

9 votes

Uniform-in-p classification* of p-groups of order p^n for each fixed n?

answered Feb 10, 2014 at 18:17

9 votes

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Dualizing the definition of a free group

answered Sep 21, 2010 at 14:19

9 votes

Statements reliant on conjectures

answered Jun 20, 2010 at 7:18

9 votes

What are your experiences of handouts in mathematics lectures?

answered Jun 7, 2010 at 20:22

8 votes

Nilpotent group with ascending and descending central series different?

answered Jul 6, 2010 at 18:09

8 votes

Induction vs. Strong Induction

answered Sep 7, 2010 at 19:16

8 votes

Unions of sets exist?

answered Nov 2, 2010 at 20:12

8 votes

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When is this diagram of tensor powers an equalizer?

answered Sep 2, 2012 at 3:38

8 votes

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Looking for a modern source about Ulm Invariants

answered Oct 23, 2015 at 16:55

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74 Answers

Measures of non-abelian-ness

Extremely messy proofs

Proof synopsis collection

Commutator subgroup does not consist only of commutators?

Groups for which the $n$-power map is a homomorphism

Non-abelian Grothendieck group

Free division rings?

Where is number theory used in the rest of mathematics?

The direct sum of injective modules need not be injective

Do these conditions on a semigroup define a group?

Is there a structure theorem or group law for finite groups generated by two elements?

Center of p-groups

Nielsen-Schreier theorem for monoids

Two abelian groups, each being direct factor of the other

Greatest power of two dividing an integer

Making N (set of all positive integers) a group

Favorite popular math book

Are the positive multiplicative group and the additive group of the field of real algebraic numbers isomorphic?

Where was it first stated that there are no 4-transitive finite groups other than symmetric, alternating and Mathieu groups?

How many "steps" does one need to obtain a group from a semigroup

Mathematical Writing: Proof Outlines/Overview in a Paper

Uniform-in-p classification* of p-groups of order p^n for each fixed n?

Dualizing the definition of a free group

Statements reliant on conjectures

What are your experiences of handouts in mathematics lectures?

Nilpotent group with ascending and descending central series different?

Induction vs. Strong Induction

Unions of sets exist?

When is this diagram of tensor powers an equalizer?

Looking for a modern source about Ulm Invariants