MathDB
Putnam 1997 A5

Source:

May 30, 2014
Putnamcollege contests

Problem Statement

Let NkN_k denote number of ordered nn-tuples of positive integers (a1,a2,,ak)(a_1,a_2, \cdots ,a_k) such that 1a1+1a2++1ak=1 \frac{1}{a_1}+\frac{1}{a_2}+\ldots +\frac{1}{a_k}=1 Determine N10N_{10} is odd or even.