2 player game with numbers <=2018 (2018 Auckland MO S4)
Source:
November 15, 2021
combinatoricsgamewinning strategyArithmetic Progression
Problem Statement
Alice and Bob are playing the following game:
They take turns writing on the board natural numbers not exceeding (to write the number twice is forbidden).
Alice begins. A player wins if after his or her move there appear three numbers on the board which are in arithmetic progression.
Which player has a winning strategy?