Polyhedral geometry of refined $q,t$-Catalan numbers

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Beck, Matthias, Hanada, Mitsuki, Hlavacek, Max, Lentfer, John, Vindas-Meléndez, Andrés R., Waddle, Katie
Format: Preprint
Veröffentlicht: 2024
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866914893939081216
author Beck, Matthias
Hanada, Mitsuki
Hlavacek, Max
Lentfer, John
Vindas-Meléndez, Andrés R.
Waddle, Katie
author_facet Beck, Matthias
Hanada, Mitsuki
Hlavacek, Max
Lentfer, John
Vindas-Meléndez, Andrés R.
Waddle, Katie
contents We study a refinement of the $q,t$-Catalan numbers introduced by Xin and Zhang (2022, 2023) using tools from polyhedral geometry. These refined $q,t$-Catalan numbers depend on a vector of parameters $\vec{k}$ and the classical $q,t$-Catalan numbers are recovered when $\vec{k} = (1,\ldots,1)$. We interpret Xin and Zhang's generating functions by developing polyhedral cones arising from constraints on $\vec{k}$-Dyck paths and their associated area and bounce statistics. Through this polyhedral approach, we recover Xin and Zhang's theorem on $q,t$-symmetry of the refined $q,t$-Catalan numbers in the cases where $\vec{k} = (k_1,k_2,k_3)$ and $(k,k,k,k)$, give some extensions, including the case $\vec{k} = (k,k+m,k+m,k+m)$, and discuss relationships to other generalizations of the $q,t$-Catalan numbers.
format Preprint
id arxiv_https___arxiv_org_abs_2407_21226
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Polyhedral geometry of refined $q,t$-Catalan numbers
Beck, Matthias
Hanada, Mitsuki
Hlavacek, Max
Lentfer, John
Vindas-Meléndez, Andrés R.
Waddle, Katie
Combinatorics
05A15 (Primary), 52B20 (Secondary)
We study a refinement of the $q,t$-Catalan numbers introduced by Xin and Zhang (2022, 2023) using tools from polyhedral geometry. These refined $q,t$-Catalan numbers depend on a vector of parameters $\vec{k}$ and the classical $q,t$-Catalan numbers are recovered when $\vec{k} = (1,\ldots,1)$. We interpret Xin and Zhang's generating functions by developing polyhedral cones arising from constraints on $\vec{k}$-Dyck paths and their associated area and bounce statistics. Through this polyhedral approach, we recover Xin and Zhang's theorem on $q,t$-symmetry of the refined $q,t$-Catalan numbers in the cases where $\vec{k} = (k_1,k_2,k_3)$ and $(k,k,k,k)$, give some extensions, including the case $\vec{k} = (k,k+m,k+m,k+m)$, and discuss relationships to other generalizations of the $q,t$-Catalan numbers.
title Polyhedral geometry of refined $q,t$-Catalan numbers
topic Combinatorics
05A15 (Primary), 52B20 (Secondary)
url https://arxiv.org/abs/2407.21226