BALTIC-WAY 1996 Problem 16
On an infinite checkerboard, two players alternately mark one unmarked cell. One of them uses , the other . The first who fills a square with his symbols wins. Can the player who starts always win?
Dataset text NuminaMath olympiads. Quoted with source.
Solutions
No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.