IMO 2013 Shortlist N6
Determine all functions f : Q ÝÑ Z satisfying f ˆ fpxq a b ˙ “ f ´x a b ¯ for all x P Q, a P Z, and b P Zą0. (Here, Zą0 ...
Category: Number Theory
Problem
Determine all functions f : Q ÝÑ Z satisfying
f
ˆ
fpxq a b ˙ “ f ´x a
b
¯
for all x P Q, a P Z, and b P Zą0. (Here, Zą0 denotes the set of positive integers.)
(Israel)