Magical mathematics: The mathematical ideas that animate great magic tricks

Authors: Persi Diaconis and Ron Graham

Published 2012 by Princeton University Press

According to Diaconis and Graham (2012), de Bruijn sequences are at the heart of several wonderful card tricks. Being unable to recall if I had come across these sequences I was glad the intention of the authors,(one a mathematician and juggler and the other a mathematician and magician), was to explain the mathematics. Nicolaas Govert de Bruijn (1918-2012) was a Dutch mathematician.

In brief the card trick involves members of the audience removing a card from the pack. The card holders indicate if their card is red (R) by standing. The performer then names the card held by each person standing. The authors explain that if the pack used has only eight cards and three audience members removed a card, there are eight possible results:

RRR RRB RBR RBB BRR BRB BBR BBB

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