TOT 487 1996 Spring J O5 2player game on 10x10 chessboard
Source:
July 9, 2024
combinatorics
Problem Statement
A game is played between two players on a checkerboard. They move alternately, the first player marking s on vacant cells and the second s. When all cells have been marked, they calculate two numbers and . is the total number of five consecutive s in a row, a column or a diagonal, so that consecutive s contribute a count of to , consecutive s contribute , and so on. Similarly, is the total number of five consecutive Os. The first player wins if , loses if and draws if . Does the first player have a strategy which guarantees
(a) a draw or a win
(b) a win
regardless of the counter-strategy of the second player?(A Belov)