Number of Modified Perfect Faro Shuffles to return Deck of Cards to Original Order/Examples/Deck of 62 Cards

From ProofWiki
Jump to navigation Jump to search

Theorem

Let $D$ be a deck of $62$ cards.

Let $D$ be given a sequence of modified perfect faro shuffles.

Then after $6$ such shuffles, the cards of $D$ will be in the same order they started in.


Proof

From Number of Modified Perfect Faro Shuffles to return Deck of Cards to Original Order, the cards of $D$ will return to their original order after $n$ such shuffles, where:

$2^n \equiv 1 \pmod {63}$

We have that:

$63 = 2^6 - 1$

and so:

$2^6 \equiv 1 \pmod {63}$

Hence the result.

$\blacksquare$


Sources