A Probabilistic Take-Away Game

Alice and Bob are playing a very simple game. Each of them starts with a pile of n chips, and they take turns to remove 1 or 2 chips from their own pile randomly and independently with equal probability. The first player who removes all chips from their pile is the winner. In this paper, we find the winning probability for Bob and analyze a new integer sequence. We also show that this game is highly disadvantageous to the second player, which is counter-intuitive. Furthermore, we study several variations of this game and determine the winning probability for Bob in each case.