Question 98
Let $N$ be a positive integer. Determine the number of pairs, $(a, b)$, of positive integers $a$ and $b$ such that the number
$$
\frac{ab}{a+b}
$$
is a divisor of $N$.
$$
\frac{ab}{a+b}
$$
is a divisor of $N$.
MathNet 2019-part-01 — 184 problems (EN–VI) Question 98
Math Olympiad Vault · MathNet 2019-part-01 — 184 problems (EN–VI)