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The Enumeration of Permutations With a Prescribed Number of ``Forbidden'' Patterns

John Noonan·Doron Zeilberger
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Abstract

We initiate a general approach for the fast enumeration of permutations with a prescribed number of occurrences of `forbidden' patterns, that seems to indicate that the enumerating sequence is always P-recursive. We illustrate the method completely in terms of the patterns `abc',`cab' and `abcd'.

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John Noonan, Doron Zeilberger. 1998-08-17. The Enumeration of Permutations With a Prescribed Number of ``Forbidden'' Patterns. https://arxiv.org/abs/math/9808080

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