MathDB
Hard NT Problem

Source: Azerbaijan Math Olympiad Training

December 15, 2019
number theoryTST

Problem Statement

Consider an odd prime number pp and pp consecutive positive integers m1,m2,,mpm_1,m_2,…,m_p. Choose a permutation σ\sigma of 1,2,,p1,2,…,p . Show that there exist two different numbers k,l(1,2,,p)k,l\in{(1,2,…,p)} such that pmk.mσ(k)ml.mσ(l)p\mid{m_k.m_{\sigma(k)}-m_l.m_{\sigma(l)}}