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Will rational tigers eat the lone sheep

Question

An island with plenty of grass holds 100100 tigers and 11 sheep. Tigers can live on grass but prefer sheep. Only one tiger can eat a sheep at a time, and a tiger that eats a sheep turns into a sheep itself. Every tiger is perfectly rational and wants above all to survive. Does the sheep get eaten?

Short answer

No. Work up from small cases: with 11 tiger the sheep is eaten; with 22, a tiger that eats becomes prey for the other, so none eats; with 33, eating leaves a safe 2-tiger situation, so one eats. By induction the sheep is eaten exactly when the number of tigers is odd, and 100100 is even.

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