game with integers, winning strategy the one who plays first
Source: Finland 2017, p4
September 8, 2019
gamecombinatoricsgame strategywinning strategy
Problem Statement
Let be a positive integer.
Two players, Axel and Elina play the game HAUKKU () proceeds as follows:
Axel starts and the players choose integers alternately. Initially, the set of integers is the set of positive divisors of a positive integer .The player in turn chooses one of the remaining numbers, and removes that number and all of its multiples from the list of selectable numbers. A player who has to choose number , loses. Show that the beginner player, Axel, has a winning strategy in the HAUKKU () game for all .PS. As member Loppukilpailija noted, it should be written , as the statement does not hold for .