MathDB
12 divides (a-b) (a-c) (a-d) (b- c) (b-d) (c-d) (1995 Chile NMO P1)

Source:

November 22, 2021
number theorydividesdivisible

Problem Statement

Let a,b,c,da,b,c,d be integers. Prove that 12 12 divides (ab)(ac)(ad)(bc)(bd)(cd) (a-b) (a-c) (a-d) (b- c) (b-d) (c-d).