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arXiv · 2108.03790

Cycles on a multiset with only even-odd drops

Zhicong Lin·Sherry H. F. Yan
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Abstract

For a finite subset $A$ of $\mathbb{Z}_{>0}$, Lazar and Wachs (2019) conjectured that the number of cycles on $A$ with only even-odd drops is equal to the number of D-cycles on $A$. In this note, we introduce cycles on a multiset with only even-odd drops and prove bijectively a multiset version of their conjecture. As a consequence, the number of cycles on $[2n]$ with only even-odd drops equals the Genocchi number $g_n$. With Laguerre histories as an intermediate structure, we also construct a bijection between a class of permutations of length $2n-1$ known to be counted by $g_n$ invented by Dumont and the cycles on $[2n]$ with only even-odd drops.

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Zhicong Lin, Sherry H. F. Yan. 2021-08-09. Cycles on a multiset with only even-odd drops. https://arxiv.org/abs/2108.03790

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