1982 USAMO #2
Source:
August 16, 2011
AMCUSA(J)MOUSAMOnumber theory unsolvednumber theory
Problem Statement
Let with real. It is known that if , (*) \frac{S_{m+n}}{m+n}=\frac{S_m}{m}\frac{S_n}{n} for , or . Determine all other pairs of integers if any, so that holds for all real numbers such that .