Question 66
How many integers between $2$ and $100$ inclusive cannot be written as $m \cdot n$, where $m$ and $n$ have no common factors and neither $m$ nor $n$ is equal to $1$? Note that there are $25$ primes less than $100$.
Math Olympiad Vault · MathNet 2008-part-05 — 164 problems (EN–VI)