MathDB
Find all functions

Source: Iran TST 2008

July 5, 2008
functionmodular arithmeticnumber theoryrelatively primefunctional equation

Problem Statement

k k is a given natural number. Find all functions f:NN f: \mathbb{N}\rightarrow\mathbb{N} such that for each m,nN m,n\in\mathbb{N} the following holds: f(m)\plus{}f(n)\mid (m\plus{}n)^k