MathDB
2player game on 1x2005 strip All-Russian MO 2005 Regional (R4) 8.2

Source:

August 26, 2024
combinatoricsgamegame strategy

Problem Statement

In the middle cell of the 1×20051 \times 2005 strip there is a chip. Two players each queues move it: first, the first player moves the piece one cell in any direction, then the second one moves it 22 cells, the 11st - by 44 cells, the 2nd by 88, etc. (the kk-th shift occurs by 2k12^{k-1} cells). That, whoever cannot make another move loses. Who can win regardless of the opponent's play?