Problem #11

Alice and Bob are playing a game in which they successively write down positive integers. They are given a target value of n; the first player to reach that value wins. Alice begins with the number 1. Players alternate turns. If the current value of the number is x, the player whose turn it is may either write down x + 1 or 2x. For which values of n can Bob force a win?

Source: IMO Candidate Problems

The solution will be posted shortly.

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