MathDB

1^{\phi (n)} + 2^{\phi (n)} +... + n^{\phi (n)} coprime with n

Source: Balkan BMO Shortlist 2016 N1

July 30, 2019

coprimephi functionnumber theoryIMO Shortlist

Problem Statement

Find all natural numbers

n

for which

1^{\phi (n)} + 2^{\phi (n)} +... + n^{\phi (n)}

is coprime with

n