Anna and Brian play a game with dominoes
Source: 2007 Swedish Mathematical Competition p5
April 27, 2021
combinatorial geometrycombinatoricsgamegame strategy
Problem Statement
Anna and Brian play a game where they put the domino tiles (of size ) in a boards composed of boxes. Tiles must be placed so that they cover exactly two boxes. Players take turnslaying each tile and the one laying last tile wins. They play once for each , where . Show that Anna wins at least of the games if she always starts first and they both always play optimally, ie if they do their best to win in every move.