23 Boxes
Source: ToT - 2001 Fall Senior A-Level #6
August 17, 2011
inductioncombinatorics unsolvedcombinatorics
Problem Statement
In a row are 23 boxes such that for , there is a box containing exactly balls. In one move, we can double the number of balls in any box by taking balls from another box which has more. Is it always possible to end up with exactly balls in the -th box for ?