MathDB
Classical game with stones

Source: BMO SL 2023 C1

May 3, 2024
combinatoricsAZE BMO TSTTST

Problem Statement

Joe and Penny play a game. Initially there are 50005000 stones in a pile, and the two players remove stones from the pile by making a sequence of moves. On the kk-th move, any number of stones between 11 and kk inclusive may be removed. Joe makes the odd-numbered moves and Penny makes the even-numbered moves. The player who removes the very last stone is the winner. Who wins if both players play perfectly?