Question 39
Determine all integers $n \ge 2$ that have a representation
$$
n = a^2 + b^2,
$$
where $a$ is the smallest divisor of $n$ different from $1$ and $b$ is an arbitrary divisor of $n$.
$$
n = a^2 + b^2,
$$
where $a$ is the smallest divisor of $n$ different from $1$ and $b$ is an arbitrary divisor of $n$.