Question 138
Find all functions $f: \mathbb{Z}_{\gt 0} \rightarrow \mathbb{Z}_{\gt 0}$ satisfying
$$
f(f(f(n))) + f(f(n)) + f(n) = 3n
$$
for all $n \in \mathbb{Z}_{\gt 0}$.
$$
f(f(f(n))) + f(f(n)) + f(n) = 3n
$$
for all $n \in \mathbb{Z}_{\gt 0}$.
MathNet 2008-part-02 — 165 problems (EN–VI) Question 138
Math Olympiad Vault · MathNet 2008-part-02 — 165 problems (EN–VI)