IMO 2018 Shortlist N6
Let f : t1,2,3,...u Ñ t2,3,...u be a fun tion su h that fpm nq | fpmq fpnq for all pairs m,n of positive integers. Prove...
Category: Number Theory
Problem
Let f : t1,2,3,...u Ñ t2,3,...u be a fun tion su h that fpm nq | fpmq fpnq for
all pairs m,n of positive integers. Prove that there exists a positive integer c ą 1 whi h divides
all values of f.
(Mexi o)