How do we approach this summation question?

Question

How do we find the following sum---

$\displaystyle\sum_{m=1}^\infty \displaystyle\sum_{n=1}^\infty \frac{mn^2}{2^n(n2^m+m2^n)}$

It was asked here with a 3 : http://math.stackexchange.com/questions/796089/double-sum-trouble — gar, Jul 10 '14 at 16:51

score 2 · Accepted Answer · answered Jul 10 '14 at 15:17

2

Yes. This problem is just a slight variant of the Putnam 1999 A4 problem. You can see the solution here:

answered Jul 10 '14 at 15:17

C.S.

1 Answers1