MathDB
Putnam 1999 A4

Source:

December 22, 2012
Putnamcalculusderivativecollege contests

Problem Statement

Sum the series m=1n=1m2n3m(n3m+m3n).\sum_{m=1}^\infty\sum_{n=1}^\infty\dfrac{m^2n}{3^m(n3^m+m3^n)}.