IMO 2023 Shortlist N1
Determine all positive, composite integers n that satisfy the following property: if the positive divisors of n are 1 “ ...
Category: Number Theory
Problem
Determine all positive, composite integers n that satisfy the following property: if
the positive divisors of n are 1 “ d1 ă d2 ă ¨¨¨ ă dk “ n, then di divides di1 di`2 for every
1 ď i ď k ´ 2.
(Colombia)