CombinatoricsDifficulty 3.0AMC 10/12Find the answerCanada
Anne and Brenda play a game which begins with a pile of n toothpicks. They alternate turns with Anne going first. On each player's turn, she must remove 1, 3 or 4 toothpicks from the pile. The player who removes the last toothpick wins the game. For which of the following values of n does Brenda have a winning strategy? (In a game, a player has a winning strategy if, regardless of what the other player does, there are moves that she can make which guarantee that she will win.)
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