Problem 2 of Third round
Source: IX International Festival of Young Mathematicians Sozopol, Theme for 10-12 grade
September 22, 2018
number theory
Problem Statement
The set of numbers of positive integers is called Sozopolian when: * p is an odd prime number * , and are different and * , and are a multiple of . a) Prove that each Sozopolian set satisfies the inequality b) Find all numbers for which there exist a Sozopolian set for which the equality of the upper inequation is met.