MathDB
Product of numbers from the set

Source: APMC 03

August 21, 2007
pigeonhole principlenumber theoryprime numberscombinatorics proposedcombinatorics

Problem Statement

Take any 26 distinct numbers from {1, 2, ... , 100}. Show that there must be a non-empty subset of the 26 26 whose product is a square.
I think that the upper limit for such subset is 37.