User DavidLHarden

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Is there a Mathieu groupoid M_31?

Jul 18 '11 at 21:48 DavidLHarden 3,377

11

votes

1

answer

328

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Maximal Sylow 2-subgroups of simple groups

gr.group-theory finite-groups

Jun 16 '17 at 11:24 Michael Giudici 1,708

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3

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(A very limited instance of) Lagrange's Theorem's converse and A_5

gr.group-theory finite-groups

Apr 17 '11 at 20:27 Derek Holt 32k

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Efficient presentations for finite groups

reference-request finite-groups

Mar 29 '11 at 19:37 Yiftach Barnea 4,798

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All maximal subgroups have odd index

gr.group-theory finite-groups

Sep 30 '16 at 22:28 Derek Holt 32k

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3k

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Orders of automorphism groups of p-groups

reference-request finite-groups gr.group-theory

Jun 19 '11 at 1:48 Jack Schmidt 9,934

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9

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3k

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Larger cycle than 4, 2, 1 in Collatz iteration?

collatz-conjecture reference-request nt.number-theory

Dec 29 at 19:16 Alexander Grigoriev 11

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The number of conjugacy classes and the order of the group

finite-groups gr.group-theory

Dec 17 '11 at 20:40 Community♦ 1

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Parker-like loop of order 2187?

gr.group-theory finite-groups

Nov 28 '11 at 2:05 Michael Kinyon 71

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Involution on sextic polynomials?

gr.group-theory galois-theory polynomials

Mar 4 '11 at 7:25 DavidLHarden 3,377

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539

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What other lattices are obtainable from this noncommutative ring?

noncommutative-rings quaternions euclidean-lattices

Jun 27 at 6:22 DavidLHarden 3,377

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3

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Counting cyclic subgroups of order $p^{2}$: $p$ an odd prime vs. $p=2$

gr.group-theory finite-groups

Jun 23 '16 at 15:41 yakov 107

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Subgroup property stronger than being characteristic

gr.group-theory finite-groups

Jul 4 '14 at 20:17 Marty Isaacs 5,929

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Jordan's Theorem on primitive permutation groups

gr.group-theory finite-groups

Jan 9 '12 at 3:08 DavidLHarden 3,377

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Does the quaternion group Q_8 have a presentation of this form?

gr.group-theory finite-groups

Jul 25 '15 at 0:01 Community♦ 1

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A solvability theorem

gr.group-theory

Jun 23 '16 at 6:38 yakov 107

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Doubly covering an even lattice

reference-request gr.group-theory euclidean-lattices finite-groups

Mar 15 '12 at 1:11 S. Carnahan♦ 42.2k

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A 'generalized Four Squares Theorem'?

euclidean-lattices nt.number-theory sums-of-squares

Aug 21 '11 at 13:38 Abhinav Kumar 2,995

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500

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The range of the Euler totient function and multiplication by 28

integer-sequences infinite-sequences

Aug 3 '18 at 7:24 Moritz Firsching 8,940

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159

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A non-commutative ring from SU(2)

reference-request euclidean-lattices ra.rings-and-algebras

Dec 30 '12 at 9:32 DavidLHarden 3,377

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2

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471

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Proving Congruence Without Leech Lattice

power-series congruences

Jan 30 '11 at 12:43 Chandan Singh Dalawat 17.7k

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1

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175

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What are these subgroups called? [closed]

gr.group-theory

Nov 23 '13 at 8:39 DavidLHarden 3,377

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0

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437

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Known and unknown about Ramanujan's tau function

reference-request modular-forms open-problems

Mar 16 '13 at 10:59 DavidLHarden 3,377

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23 Questions

Is there a Mathieu groupoid M_31?

Maximal Sylow 2-subgroups of simple groups

(A very limited instance of) Lagrange's Theorem's converse and A_5

Efficient presentations for finite groups

All maximal subgroups have odd index

Orders of automorphism groups of p-groups

Larger cycle than 4, 2, 1 in Collatz iteration?

The number of conjugacy classes and the order of the group

Parker-like loop of order 2187?

Involution on sextic polynomials?

What other lattices are obtainable from this noncommutative ring?

Counting cyclic subgroups of order $p^{2}$: $p$ an odd prime vs. $p=2$

Subgroup property stronger than being characteristic

Jordan's Theorem on primitive permutation groups

Does the quaternion group Q_8 have a presentation of this form?

A solvability theorem

Doubly covering an even lattice

A 'generalized Four Squares Theorem'?

The range of the Euler totient function and multiplication by 28

A non-commutative ring from SU(2)

Proving Congruence Without Leech Lattice

What are these subgroups called? [closed]

Known and unknown about Ramanujan's tau function