# Maisam Hedyelloo

Iran

mathoverflow.blogfa.com

Age: 26

Top Questions
24 votes

## How to prove that $\frac{(5m)!(5n)!}{(m!)(n!)(3m+n)!(3n+m)!}$ is a natural number?

asked Mar 20 '13 at 20:01

18 votes

18 votes

## How to compute the series $\sum\limits_{x=0}^\infty\sum\limits_{y=0}^\infty\sum\limits_{z=0}^\infty\frac{1}{2^x(2^{x+y}+2^{x+z}+2^{z+y})}$

asked Jan 24 '13 at 19:07

18 votes

## How to prove that $\frac{(mn)!}{m!(n!)^m}$ is an integer?

asked Feb 23 '13 at 18:41

17 votes

14 votes

## A group such that $a^m b^m = b^m a^m$ and $a^n b^n = b^n a^n$ ($m$, $n$ coprime) is abelian?

asked Mar 10 '13 at 18:47

14 votes

## how to integrate $\int\underbrace{x^{x^{\cdot^{\cdot^x}}}}_ndx$

asked Jun 23 '13 at 20:18

13 votes

13 votes

## how to solve $1!+2!+3!+…+x!=y^{z+1}$where $x,y,z\in \mathbb N$?

asked Mar 23 '13 at 19:32

12 votes

## Let the matrix $A=[a_{ij}]_{n×n}$ be defined by $a_{ij}=\gcd(i,j )$. How prove that $A$ is invertible, and compute $\det(A)$?

asked Feb 10 '13 at 19:59