Generalizations of two-stack-sortable permutations

Dapeng Xu

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Generalizations of two-stack-sortable permutations

Dapeng Xu

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Abstract

In this thesis, we apply the stack sorting operator to $r$-permutations and construct the functional equation for the generating function of two-stack-sortable $k$-tuple $r$-permutations counted by descents by using a factorization similar to Zeilberger's. We solve the functional equation and give explicit formulas for the number of two-stack-sortable $r$-permutations.

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Dapeng Xu. 2002-09-25. Generalizations of two-stack-sortable permutations. https://arxiv.org/abs/math/0209313

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