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arXiv · 1802.09856

On (shape-)Wilf-equivalence for words

Ting Guo·Christian Krattenthaler·Yi Zhang
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Abstract

Stankova and West showed that for any non-negative integer $s$ and any permutation $γ$ of $\{4,5,\dots,s+3\}$ there are as many permutations that avoid $231γ$ as there are that avoid $312γ$. We extend this result to the setting of words.

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Ting Guo, Christian Krattenthaler, Yi Zhang. 2018-06-01. On (shape-)Wilf-equivalence for words. https://arxiv.org/abs/1802.09856

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