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arXiv · 2404.04091

Bijections on pattern avoiding inversion sequences and related objects

JiSun Huh·Sangwook Kim·Seunghyun Seo·Heesung Shin
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Abstract

The number of inversion sequences avoiding two patterns $101$ and $102$ is known to be the same as the number of permutations avoiding three patterns $2341$, $2431$, and $3241$. This sequence also counts the number of Schröder paths without triple descents, restricted bicolored Dyck paths, $(101,021)$-avoiding inversion sequences, and weighted ordered trees. We provide bijections to integrate them together by introducing $F$-paths. Moreover, we define three kinds of statistics for each of the objects and count the number of each object with respect to these statistics. We also discuss direct sums of each object.

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JiSun Huh, Sangwook Kim, Seunghyun Seo, Heesung Shin. 2024-04-05. Bijections on pattern avoiding inversion sequences and related objects. https://arxiv.org/abs/2404.04091

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