Problem

Source: Bundeswettbewerb Mathematik 2017, Round 1 - #1

Tags: blackboard, combinatorics, combinatorics unsolved, number theory, number theory unsolved, divisible, Divisibility



The numbers $1,2,3,\dots,2017$ are on the blackboard. Amelie and Boris take turns removing one of those until only two numbers remain on the board. Amelie starts. If the sum of the last two numbers is divisible by $8$, then Amelie wins. Else Boris wins. Who can force a victory?