Beautiful set
Source: IMAR 2017, Problem 3
November 18, 2017
Problem Setscombinatorics
Problem Statement
We consider a set of odd positive interger numbers with elements such that no element divides another element. We say that a set is if for any 3 elements from , there is one the divides the sum of the other 2. We call a beautiful set if we can't add another number to the set such that will still be beautiful. Find the values of for which there exists a set.