A positive integer is written on a blackboard. Players A and B play the following game: in each move one has to choose a proper divisor m of the number n written on the blackboard (1<m<n) and replaces n with nām. Player A makes the first move, then players move alternately. The player who can't make a move loses the game. For which starting numbers is there a winning strategy for player B? inductionstrong inductioncombinatorics unsolvedcombinatorics