2023 APMO Problems/Problem 2

Problem

Find all integers $n$ satisfying $n \ge 2$ and $\frac{\sigma(n)}{p(n)-1}=n$ , 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

Page

Toolbox

Search

2023 APMO Problems/Problem 2

Problem

Solution