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2023 APMO Problems/Problem 2

Revision as of 21:51, 19 August 2023 by Renrenthehamster (talk | contribs) (Created page with "==Problem== Find all integers <math>n</math> satisfying <math>n \ge 2</math> and <math>\frac{\sigma(n)}{p(n)-1}, in which </math>\sigma(n)<math> denotes the sum of all positi...")
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Problem

Find all integers $n$ satisfying $n \ge 2$ and $\frac{\sigma(n)}{p(n)-1}, in which$\sigma(n)$denotes the sum of all positive divisors of$n$, and$p(n)$denotes the largest prime divisor of$n$.

Solution

https://youtu.be/xkIm0k1FE-8

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