MathDB
2010 PUMaC NT A4: n*phi(n) is perfect square

Source:

August 22, 2011
number theoryrelatively prime

Problem Statement

Find the largest positive integer nn such that nφ(n)n\varphi(n) is a perfect square. (φ(n)\varphi(n) is the number of integers kk, 1≤k≤n1 \leq k \leq n that are relatively prime to nn)
Back to ProblemsView on AoPS