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MathNet 2022-part-06 — 196 problems (EN–VI) Question 87

Math Olympiad Vault · MathNet 2022-part-06 — 196 problems (EN–VI)

Question 87

Call a positive integer $n$ quixotic if the value of
$$
\operatorname{lcm}(1,2,3, \ldots, n) \cdot\left(\frac{1}{1}+\frac{1}{2}+\frac{1}{3}+\ldots+\frac{1}{n}\right)
$$
is divisible by $45$. Compute the tenth smallest quixotic integer.