User David E Speyer - MathOverflow

123 votes

5 answers

34k views

How did Cole factor $2^{67}-1$ in 1903?

asked May 22, 2015 at 15:33

75 votes

9 answers

17k views

What is Lagrange Inversion good for?

asked Jul 16, 2010 at 1:25

64 votes

3 answers

8k views

Is there a "Basic Number Theory" for elliptic curves?

asked Jul 31, 2011 at 15:15

51 votes

6 answers

2k views

Why does $d^n \exp(-x-x^{-1})/(dx)^n$ only have $n$ positive real zeroes?

asked Aug 19, 2015 at 15:45

36 votes

2 answers

2k views

Is it consistent with ZF that $V \to V^{\ast \ast}$ is always an isomorphism?

asked Jan 11, 2018 at 14:29

36 votes

3 answers

4k views

What is the right version of "partitions of unity implies vanishing sheaf cohomology"

asked Jan 12, 2010 at 17:48

33 votes

3 answers

4k views

Can assignment solve stable marriage?

asked Nov 12, 2010 at 15:04

33 votes

0 answers

2k views

Is there software to compute the cohomology of an affine variety?

asked Nov 16, 2011 at 21:17

33 votes

3 answers

2k views

A double grading of catalan numbers

asked May 25, 2013 at 3:22

32 votes

0 answers

1k views

Is every $p$-group the $\mathbb{F}_p$-points of a unipotent group

asked Feb 21, 2017 at 3:26

31 votes

1 answer

1k views

Finding a path through real rooted polynomials

asked May 29, 2015 at 19:10

31 votes

4 answers

5k views

Rolling without slipping interpretation of torsion

asked Jan 26, 2011 at 19:10

31 votes

6 answers

5k views

What is known about this plethysm?

asked May 4, 2010 at 0:33

30 votes

0 answers

814 views

Is there an Ehrhart polynomial for Gaussian integers

asked May 12, 2014 at 1:46

28 votes

2 answers

3k views

Why not define triangulated categories using a mapping cone functor?

asked Mar 9, 2011 at 2:08

27 votes

4 answers

3k views

Do Abel summation and zeta summation always coincide?

asked Mar 26, 2010 at 12:24

27 votes

5 answers

4k views

What is induction up to $\varepsilon_0$?

asked Nov 11, 2009 at 16:02

27 votes

8 answers

6k views

Conceptual algebraic proof that Grassmannian is closed in Plücker embedding

asked Sep 18, 2014 at 1:44

25 votes

2 answers

2k views

Direct proof that the centralizer of $GL(V)$ acting on $V^{\otimes n}$ is spanned by $S_n$

asked Mar 3, 2012 at 0:43

24 votes

2 answers

3k views

Calculating Mayer-Vietoris efficiently

asked Mar 15, 2012 at 0:51

24 votes

2 answers

4k views

Is there a 7-regular graph on 50 vertices with girth 5? What about 57-regular on 3250 vertices?

asked Oct 28, 2010 at 1:42

22 votes

2 answers

1k views

Are there any natural differential operators besides $d$?

asked Mar 22, 2015 at 18:51

22 votes

0 answers

810 views

A Green's function for the Laplacian on k-forms

asked Sep 9, 2020 at 4:01

21 votes

1 answer

2k views

A spectral sequence for computing cohomology of a space from that of its strata

asked Mar 7, 2016 at 22:56

21 votes

2 answers

1k views

If a polynomial ring is finite free over a subring, is the subring polynomial?

asked Oct 5, 2017 at 18:11

21 votes

4 answers

2k views

Rhombus tilings with more than three directions

asked Oct 17, 2011 at 2:00

21 votes

7 answers

4k views

Whitehead for maps

asked Oct 26, 2009 at 20:32

20 votes

3 answers

2k views

Simple example of a ring which is normal but not CM

asked Oct 21, 2009 at 13:42

20 votes

1 answer

1k views

When should I expect a quiver with potential to be rigid?

asked Oct 21, 2009 at 14:37

20 votes

2 answers

1k views

Hopf algebra reference

asked Oct 22, 2009 at 22:30

Stack Exchange Network

133 Questions

How did Cole factor $2^{67}-1$ in 1903?

What is Lagrange Inversion good for?

Is there a "Basic Number Theory" for elliptic curves?

Why does $d^n \exp(-x-x^{-1})/(dx)^n$ only have $n$ positive real zeroes?

Is it consistent with ZF that $V \to V^{\ast \ast}$ is always an isomorphism?

What is the right version of "partitions of unity implies vanishing sheaf cohomology"

Can assignment solve stable marriage?

Is there software to compute the cohomology of an affine variety?

A double grading of catalan numbers

Is every $p$-group the $\mathbb{F}_p$-points of a unipotent group

Finding a path through real rooted polynomials

Rolling without slipping interpretation of torsion

What is known about this plethysm?

Is there an Ehrhart polynomial for Gaussian integers

Why not define triangulated categories using a mapping cone functor?

Do Abel summation and zeta summation always coincide?

What is induction up to $\varepsilon_0$?

Conceptual algebraic proof that Grassmannian is closed in Plücker embedding

Direct proof that the centralizer of $GL(V)$ acting on $V^{\otimes n}$ is spanned by $S_n$

Calculating Mayer-Vietoris efficiently

Is there a 7-regular graph on 50 vertices with girth 5? What about 57-regular on 3250 vertices?

Are there any natural differential operators besides $d$?

A Green's function for the Laplacian on k-forms

A spectral sequence for computing cohomology of a space from that of its strata

If a polynomial ring is finite free over a subring, is the subring polynomial?

Rhombus tilings with more than three directions

Whitehead for maps

Simple example of a ring which is normal but not CM

When should I expect a quiver with potential to be rigid?

Hopf algebra reference