A shuffle is a rearrangement of the elements in an ordered list, often used to randomize a deck of cards. A riffle
shuffle interleaves two packets while preserving the order within each packet.
Shuffling by successively interchanging the cards in position
1, 2, ...,
with cards in randomly chosen positions is known as an
exchange shuffle. Normal shuffling leaves gaps
of different lengths between the two layers of cards and
so randomizes the order of the cards.
Keller (1995) showed that roughly shuffles are needed just to randomize the bottom card.
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with cards in randomly chosen positions is known as an
exchange shuffle. Normal shuffling leaves gaps
of different lengths between the two layers of cards and
so randomizes the order of the cards.
shuffles are needed just to randomize the bottom card.
." 6 Oct 2000.