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2019 Discrete Tiebreaker #3

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October 5, 2022
2019Discrete Math Tiebreaker

Problem Statement

55 monkeys, 55 snakes, and 55 tigers are standing in line at the local grocery store, with animals of the same species being indistinguishable. A monkey stands at the front of the line and a tiger stands at the end of the line. Unfortunately, monkeys and tigers are sworn enemies, so monkeys and tigers cannot stand in adjacent places in line. Compute the number of possible arrangements of the line.