MathDB
Combinatorial Game

Source: Baltic Way 2015

November 8, 2015
winning positionsCombinatorial gamescombinatorics

Problem Statement

Two players play the following game. At the outset there are two piles, containing 10,00010,000 and 20,00020,000 tokens,respectively . A move consists of removing any positive number of tokens from a single pile oror removing x>0x>0 tokens from one pile and y>0y>0 tokens from the other , where x+yx+y is divisible by 20152015. The player who can not make a move loses. Which player has a winning strategy