David Speyer

Associate professor of math at UMich, very active on Mathoverflow.

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Can we get notification of answers to questions where we have offered bounties?

feature-request status-completed bounty asked Oct 2 '11 at 16:48

meta.stackoverflow.com

14 votes

How to compute rational or integer points on elliptic curves

reference-request diophantine-equations math-software elliptic-curves faq asked Sep 27 '12 at 14:42

math.stackexchange.com

14 votes

Can extending a finite ground field make modules isomorphic?

abstract-algebra modules finite-fields asked Feb 16 at 19:25

math.stackexchange.com

13 votes

Writing a group element as $ghg^{-1} h^{-1}$ and as $g^2 h^2$

abstract-algebra group-theory finite-groups representation-theory alternative-proof asked Apr 18 at 14:13

math.stackexchange.com

12 votes

If a finite group $G$ is solvable, is $[G,G]$ nilpotent?

group-theory finite-groups solvable-groups asked Jan 8 at 14:50

math.stackexchange.com

12 votes

How can I show a Gap-P problem is outside #P

cc.complexity-theory counting-complexity lower-bounds asked Sep 11 '11 at 13:41

cstheory.stackexchange.com

11 votes

Why can't I use Sequence to perform a Select like task?

list-manipulation syntax asked Nov 13 '12 at 18:52

mathematica.stackexchange.com

7 votes

Covering a group with the conjugates of two subgroups related by an automorphism

group-theory finite-groups asked Apr 14 at 15:20

math.stackexchange.com

6 votes

Interpolating between Krull-Schmidt and Jordan-Holder

group-theory asked Jan 8 at 21:38

math.stackexchange.com

5 votes

How to express the original ideal elements in the Groebner basis?

polynomials groebner-bases asked Aug 14 '12 at 19:38

mathematica.stackexchange.com

Top Answers

Is it morally right and pedagogically right to google answers to homework?

math.stackexchange.com

Advantages of IMO students in Mathematical Research

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Convergence of $\sqrt{n}x_{n}$ where $x_{n+1} = \sin(x_{n})$

math.stackexchange.com

Convergence of $\sum \limits_{n=1}^{\infty}\sin(n^k)/n$

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Different methods to compute $\sum\limits_{n=1}^\infty \frac{1}{n^2}$

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Sums of roots of unity

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The $5n+1$ Problem

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Striking applications of integration by parts

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Distance from $x^n$ to lesser polynomials

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Is there a limit of cos (n!)?

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GrossOne? The arXiv blog's pick of the day.

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Can I use Ravi Vakil's way of learning for elementary subjects?

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What does the Hodge conjecture mean?

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When is $1^5 + 2^5 + \ldots + n^5$ a square?

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Intuition behind the “large but finite search space” of the proof of the four colour theorem?

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Machin's formula and cousins

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Three finite groups with the same numbers of elements of each order

math.stackexchange.com

Is “converges at” idiomatic English in some regions?

math.stackexchange.com

MathOverflow.net: How can we get members of this site and the SO/SF/SU sites to stop recommending it inappropriately?

meta.stackoverflow.com

Why some people don't like proofs by contradiction

math.stackexchange.com

Why are harmonic functions called harmonic functions?

math.stackexchange.com

A discrete math riddle

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Mathematical difference between white and black notes in a piano

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Do your friends on average have more friends than you do?

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Is there a clean way to extract the subspaces invariant under a list of matrices?

mathematica.stackexchange.com

How can I read this mathematical sentence aloud in English?

math.stackexchange.com

Difference between undecidable statements in set-theory and number theory?

math.stackexchange.com

What are the most common pitfalls awaiting new users?

mathematica.stackexchange.com

What is the probability of a coin landing tails 7 times in a row in a series of 150 coin flips?

math.stackexchange.com

Elementary proof that $2x^2+xy+3y^2$ represents infinitely many primes?

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