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arXiv · 2607.04111

The last distribution-equivalence class of mesh patterns of length 2

Zuo-Ru Zhang·Hongkuan Zhao
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Abstract

We prove the remaining conjectural distribution-equivalence of mesh patterns of length 2 from 2019. This completes the classification of distribution-equivalence and Wilf-equivalence classes for mesh patterns of length 2. Consequently the numbers of such classes are 105 and 46, respectively. We approach this by constructing a marked occurrence bijection, in the spirit of the cluster method for consecutive patterns.

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Zuo-Ru Zhang, Hongkuan Zhao. 2026-07-05. The last distribution-equivalence class of mesh patterns of length 2. https://arxiv.org/abs/2607.04111

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