Wolfram Function Repository
Instantuse addon functions for the Wolfram Language
Function Repository Resource:
Perform an in shuffle on a list
ResourceFunction["InShuffle"][list] performs an in shuffle on list. 

ResourceFunction["InShuffle"][list,n] performs n in shuffles on list. 
Perform an in shuffle on a list of 10 items:
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Perform an in shuffle 3 times to a list:
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Confirm that this is the same:
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The list can contain expressions of different type:
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Create a sorted deck of cards:
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Shuffle the deck once:
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The original is obtained after 52 shuffles:
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An in shuffle on a list of length 2 can be seen as swapping the elements or reversing the list:
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Figure out after how many in shuffles a list of size n returns to its original order:
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For lists of even length, the number of shuffles to return to the original order is known analytically:
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Visualize how the positions of items are changed for a list of length 21 in the form of a Graph:
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Confirm that 6 nested in shuffles returns the list of 21 items to the original order:
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Zero iterations returns the original list:
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Plot how many in shuffles are needed to return to the original order for a list of length n:
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Wolfram Language 11.3 (March 2018) or above
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