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Sean Eberhard

Belfast, UK

http://www.randompermutations.com

My hobbies include doing research mathematics, doing elementary mathematics, writing things in latex, cooking, correcting grammar, and being skeptical. Fortunately there is a stackexchange website for each of these compulsions.

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Top Questions
22 votes

Possible limits of $(1/n) \sum_{k=0}^{n-1} e^{i2\pi \cdot 2^k\alpha}$

ds.dynamical-systems ergodic-theory limits-and-convergence asked Feb 19, 2016 at 11:32
mathoverflow.net

22 votes

Probability of satisfying a word in a compact group

gr.group-theory lie-groups asked Oct 13, 2018 at 16:02
mathoverflow.net

17 votes

What is the length of the shortest law of $S_n$?

gr.group-theory symmetric-group combinatorial-group-theor asked Apr 10, 2013 at 11:14
mathoverflow.net

12 votes

General Isoperimetric Inequality via Representation Theory of SO(n)

rt.representation-theory dg.differential-geometry isoperimetry fourier-analysis asked Jan 26, 2012 at 21:51
mathoverflow.net

11 votes

A trick or a general technique? (Probabilistic Method)

co.combinatorics pr.probability asked Jan 15, 2012 at 11:48
mathoverflow.net

11 votes

Lower central series of a free group

group-theory free-groups computational-algebra asked Apr 16, 2013 at 12:41
math.stackexchange.com

10 votes

Maximize $f(0)+\cdots+f(n-1)$ subject to $f(x)f(y) + f(x+y) \leq 1$

additive-combinatorics nonlinear-optimization asked Dec 22, 2018 at 18:37
mathoverflow.net

10 votes

Regular subsets of $\text{PSL}(2, q)$

co.combinatorics gr.group-theory group-actions asked Aug 15, 2019 at 9:26
mathoverflow.net

10 votes

Representations of $\text{SL}_n(q)$ of degree $q^{O(n)}$

rt.representation-theory deligne-lusztig-theory asked Dec 16, 2019 at 15:24
mathoverflow.net

10 votes

Sum of a Poisson point process

pr.probability asked Nov 4, 2022 at 15:16
mathoverflow.net

1 2 3

Top Answers
35
If $a^2$ divides $b^2$, then $a$ divides $b$
math.stackexchange.com

27
Function that produces primes
mathoverflow.net

23
ord $(b)|\max\{\text{ord}(g)|g\in G\}$ for all $b\in G\,$ a finite abelian group
math.stackexchange.com

23
morphism from a compact group to Z ?
mathoverflow.net

22
A rather curious identity on sums over triple binomial terms
mathoverflow.net

21
How does Sage order the elements of the symmetric group?
mathoverflow.net

21
Difference between pushforward and differential
math.stackexchange.com

18
$K_6$ contains at least two monochromatic $K_3$ graphs.
math.stackexchange.com

17
A set of positive measure with cardinality less than that of the continuum?
mathoverflow.net

16
Are there $2^{\aleph_0}$ pairwise non-isomorphic countable groups containing every finite group?
mathoverflow.net

16
Haar's theorem for the rotation-invariant distribution on the sphere
math.stackexchange.com

15
Test if a finite group is a symmetric group algorithmically
math.stackexchange.com

15
Seating of $n$ people with tickets into $n+k$ chairs with 1st person taking a random seat
math.stackexchange.com

15
Show that $ \lim\limits_{n\to\infty}\frac{1}{n}\sum\limits_{k=0}^{n-1}e^{ik^2}=0$
math.stackexchange.com

13
Speed of convergence of $\zeta(2k)\to 1$?
mathoverflow.net

12
Conjugacy classes in towers of groups
mathoverflow.net

12
How quasirandom are the nonabelian finite simple groups?
mathoverflow.net

12
Why is this sequence of functions not uniformly convergent?
math.stackexchange.com

12
Maximal Number of Pairs of Orthogonal vectors in a set of $n$ vectors in $\mathbb{R}^3$
mathoverflow.net

11
A sumset inequality
mathoverflow.net

10
A question about expander graphs
mathoverflow.net

10
How to prove that $2+2 = 2*2 = 2^2 \cdots= 4$
math.stackexchange.com

10
A Hölder like inequality
mathoverflow.net

10
Is this function nowhere differentiable?
math.stackexchange.com

10
Functions sending subgroups to subgroups
math.stackexchange.com

10
How many non-isomorphic abelian subgroups of the permutation group $S_n$?
mathoverflow.net

10
Elementary inhomogeneous inequality for three non-negative reals
mathoverflow.net

10
Functions $f$ on $\mathbb{Z}/N\mathbb{Z}$ with $|f|$ and $|\widehat{f}|$ constant
mathoverflow.net

10
Probability of commutation in a compact group
mathoverflow.net

10
What is the smallest cardinality of a self-linked set in a finite cyclic group?
mathoverflow.net

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