Question 113
Let $a$, $b$, $c$ be three integers such that $a+b+c$ is divisible by $13$. Show that too
$$
a^{2007} + b^{2007} + c^{2007} + 2 \cdot 2007 a b c
$$
is divisible by $13$.
$$
a^{2007} + b^{2007} + c^{2007} + 2 \cdot 2007 a b c
$$
is divisible by $13$.