Operators of equivalent sorting power and related Wilf-equivalences

Autor: Michael Albert, Mathilde Bouvel
Jazyk: angličtina
Rok vydání: 2013
Předmět:
Zdroj: Discrete Mathematics & Theoretical Computer Science, Vol DMTCS Proceedings vol. AS,..., Iss Proceedings (2013)
Druh dokumentu: article
ISSN: 1365-8050
DOI: 10.46298/dmtcs.2333
Popis: We study sorting operators $\textrm{A}$ on permutations that are obtained composing Knuth's stack sorting operator \textrmS and the reverse operator $\textrm{R}$, as many times as desired. For any such operator $\textrm{A}$, we provide a bijection between the set of permutations sorted by $\textrm{S} \circ \textrm{A}$ and the set of those sorted by $\textrm{S} \circ \textrm{R} \circ \textrm{A}$, proving that these sets are enumerated by the same sequence, but also that many classical permutation statistics are equidistributed across these two sets. The description of this family of bijections is based on an apparently novel bijection between the set of permutations avoiding the pattern $231$ and the set of those avoiding $132$ which preserves many permutation statistics. We also present other properties of this bijection, in particular for finding families of Wilf-equivalent permutation classes.
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