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MathNet 2008-part-05 — 164 problems (EN–VI) Question 26

Math Olympiad Vault · MathNet 2008-part-05 — 164 problems (EN–VI)

Question 26

Call a number overweight if it has at least three positive integer divisors (including $1$ and the number), and call a number obese if it has at least four positive integer divisors (including $1$ and the number). How many positive integers between $1$ and $200$ are overweight, but not obese?