The number 102007 is written on the blackboard. Anne and Berit play a two player game in which the player in turn performs one of the following operations:
1) replace a number x on the blackboard with two integers a,b>1 such that ab=x.
2) strike off one or both of two equal numbers on the blackboard.The person who cannot perform any operation loses.
Who has the winning strategy if Anne starts? combinatorics unsolvedcombinatorics