Permutation Tableaux and the Dashed Permutation Pattern 32-1

William Y. C. Chen; Lewis H. Liu

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arXiv · 1007.5019

Permutation Tableaux and the Dashed Permutation Pattern 32-1

William Y. C. Chen·Lewis H. Liu

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Abstract

We give a solution to a problem posed by Corteel and Nadeau concerning permutation tableaux of length n and the number of occurrences of the dashed pattern 32--1 in permutations on [n]. We introduce the inversion number of a permutation tableau. For a permutation tableau T and the permutation $\pi$ obtained from T by the bijection of Corteel and Nadeau, we show that the inversion number of T equals the number of occurrences of the dashed pattern 32--1 in the reverse complement of $\pi$. We also show that permutation tableaux without inversions coincide with L-Bell tableaux introduced by Corteel and Nadeau.

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William Y. C. Chen, Lewis H. Liu. 2010-07-28. Permutation Tableaux and the Dashed Permutation Pattern 32-1. https://arxiv.org/abs/1007.5019

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