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arXiv · 2003.06269

On a combinatorial problem in the Secret Santa ritual

Alexander Steinicke·Markus Penz·Bine Penz
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Abstract

The Secret Santa ritual, where in a group of people every member presents a gift to a randomly assigned partner, poses a combinatorial problem when considering the probabilities involved in the formation of pairs, where two persons exchange gifts mutually. We give different possible derivations for such probabilities by counting fixed-point-free permutations with certain numbers of 2-cycles.

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Alexander Steinicke, Markus Penz, Bine Penz. 2020-03-11. On a combinatorial problem in the Secret Santa ritual. https://arxiv.org/abs/2003.06269

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