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arXiv · 2503.22098

Proof of a conjecture on the shape-Wilf-equivalence for partially ordered patterns

Lintong Wang·Sherry H. F. Yan
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Abstract

A partially ordered pattern (abbreviated POP) is a partially ordered set (poset) that generalizes the notion of a pattern when we are not concerned with the relative order of some of its letters. The notion of partially ordered patterns provides a convenient language to deal with large sets of permutation patterns. In analogy to the shape-Wilf-equivalence for permutation patterns, Burstein-Han-Kitaev-Zhang initiated the study of the shape-Wilf-equivalence for POPs which would result in the shape-Wilf-equivalence for large sets of permutation patterns. The main objective of this paper is to confirm a recent intriguing conjecture posed by Burstein-Han-Kitaev-Zhang concerning the shape-Wilf-equivalence for POPs of length $k$. This is accomplished by establishing a bijection between two sets of pattern-avoiding transversals of a given Young diagram.

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Lintong Wang, Sherry H. F. Yan. 2025-03-28. Proof of a conjecture on the shape-Wilf-equivalence for partially ordered patterns. https://doi.org/10.1016/j.ejc.2025.104222

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