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arXiv · 0908.3462

A rule of thumb for riffle shuffling

Sami Assaf·Persi Diaconis·K. Soundararajan
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Abstract

We study how many riffle shuffles are required to mix n cards if only certain features of the deck are of interest, e.g. suits disregarded or only the colors of interest. For these features, the number of shuffles drops from 3/2 log_2(n) to log_2(n). We derive closed formulae and an asymptotic `rule of thumb' formula which is remarkably accurate.

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Sami Assaf, Persi Diaconis, K. Soundararajan. 2009-08-24. A rule of thumb for riffle shuffling. https://doi.org/10.1214/10-aap701

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