MathDB
Putnam 1993 B6

Source: Putnam 1993

July 18, 2022
Putnaminvariantcombinatorics

Problem Statement

Let SS be a set of three, not necessarily distinct, positive integers. Show that one can transform SS into a set containing 00 by a finite number of applications of the following rule: Select two of the integers xx and yy, where xyx\leq y and replace them with 2x2x and yx.y-x.