IMO Shortlist 1969 problem 54
Dodao/la:
arhiva2. travnja 2012. 
Given a polynomial

with integer coefficients whose value is divisible by

for three integers

and

. Prove that

is divisible by

for all integers
%V0
$(POL 3)$ Given a polynomial $f(x)$ with integer coefficients whose value is divisible by $3$ for three integers $k, k + 1,$ and $k + 2$. Prove that $f(m)$ is divisible by $3$ for all integers $m.$
Izvor: Međunarodna matematička olimpijada, shortlist 1969