Chain Decompositions of q, t-Catalan Numbers: Tail Extensions and Flagpole Partitions
Chain Decompositions of q, t-Catalan Numbers: Tail Extensions and Flagpole Partitions
复制标题
q, t-加泰罗尼亚数的链分解:尾部扩展和旗杆分区
DOI:
10.1007/s00026-022-00590-7
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发表时间:
2022
影响因子:
0.5
通讯作者:
Loehr, Nicholas A.
中科院分区:
文献类型:
--
作者:
Han, Seongjune;Lee, Kyungyong;Li, Li;Loehr, Nicholas A.
This article is part of an ongoing investigation of the combinatorics ofq,t-Catalan numbers. We develop a structure theory for integer partitions based on the partition statistics dinv, deficit, and minimum triangle height. Our goal is to decompose the infinite set of partitions of deficitkinto a disjoint union of chainsindexed by partitions of sizek. Among other structural properties, these chains can be paired to give refinements of the famous symmetry property. Previously, we introduced a map that builds the tail part of each chain. Our first main contribution here is to extend this map to construct larger second-order tails for each chain. Second, we introduce new classes of partitions called flagpole partitions and generalized flagpole partitions. Third, we describe a recursive construction for building the chainfor a (generalized) flagpole partition, assuming that the chains indexed by certain specific smaller partitions (depending on) are already known. We also give some enumerative and asymptotic results for flagpole partitions and their generalized versions.