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arXiv · 2101.10147

There are EXACTLY 1493804444499093354916284290188948031229880469556 Ways to Derange a Standard Deck of Cards (ignoring suits) [and many other such useful facts]

Shalosh B. Ekhad·Christoph Koutschan·Doron Zeilberger
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Abstract

In this memorial tribute to Joe Gillis, who taught us that Special Functions count, we show how the seminal Even-Gillis integral formula for the number of derangements of a multiset, in terms of Laguerre polynomials, can be used to efficiently compute not only the number of the title, but much harder ones, when it is interfaced with Wilf-Zeilberger algorithmic proof theory.

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Shalosh B. Ekhad, Christoph Koutschan, Doron Zeilberger. 2021-01-25. There are EXACTLY 1493804444499093354916284290188948031229880469556 Ways to Derange a Standard Deck of Cards (ignoring suits) [and many other such useful facts]. https://arxiv.org/abs/2101.10147

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