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nice question 2

Source: iran tst 2014 third exam

May 22, 2014
functionnumber theoryprime numbersnumber theory proposed

Problem Statement

is there a function f:NNf:\mathbb{N}\rightarrow \mathbb{N} such that i)nN:f(n)ni) \exists n\in \mathbb{N}:f(n)\neq n ii)ii) the number of divisors of mm is f(n)f(n) if and only if the number of divisors of f(m)f(m) is nn