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DavidLHarden
  • Member for 13 years, 2 months
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10 votes
2 answers
4k views

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

8 votes
3 answers
616 views

What other lattices are obtainable from this noncommutative ring?

4 votes
1 answer
1k views

The range of the Euler totient function and multiplication by 28

12 votes
1 answer
451 views

Maximal Sylow 2-subgroups of simple groups

10 votes
1 answer
667 views

All maximal subgroups have odd index

7 votes
3 answers
2k views

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

5 votes
1 answer
1k views

A solvability theorem

7 votes
1 answer
2k views

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

7 votes
2 answers
438 views

Subgroup property stronger than being characteristic

0 votes
1 answer
177 views

What are these subgroups called? [closed]

0 votes
0 answers
554 views

Known and unknown about Ramanujan's tau function

3 votes
0 answers
163 views

A non-commutative ring from SU(2)

5 votes
2 answers
276 views

Doubly covering an even lattice

7 votes
0 answers
897 views

Jordan's Theorem on primitive permutation groups

9 votes
3 answers
3k views

The number of conjugacy classes and the order of the group

9 votes
2 answers
465 views

Parker-like loop of order 2187?

5 votes
1 answer
546 views

A 'generalized Four Squares Theorem'?

32 votes
0 answers
958 views

Is there a Mathieu groupoid M_31?

10 votes
2 answers
4k views

Orders of automorphism groups of p-groups

11 votes
3 answers
903 views

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

11 votes
4 answers
1k views

Efficient presentations for finite groups

8 votes
0 answers
239 views

Involution on sextic polynomials?

2 votes
2 answers
488 views

Proving Congruence Without Leech Lattice