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sum of all numbers on the paper having exactly 2 proper divisors v2

Source: 2020 Dürer Math Competition Finals Day2 E+5 https://artofproblemsolving.com/community/c1622639_2020_

January 7, 2022
number theorydivisor

Problem Statement

On a piece of paper, we write down all positive integers nn such that all proper divisors of nn are less than 3030. We know that the sum of all numbers on the paper having exactly one proper divisor is 23972397. What is the sum of all numbers on the paper having exactly two proper divisors?
We say that kk is a proper divisor of the positive integer nn if k∣nk | n and 1<k<n1 < k < n.
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