English

Partitions and Partial Matchings Avoiding Neighbor Patterns

Combinatorics 2010-09-24 v1

Abstract

We obtain the generating functions for partial matchings avoiding neighbor alignments and for partial matchings avoiding neighbor alignments and left nestings. We show that there is a bijection between partial matchings avoiding three neighbor patterns (neighbor alignments, left nestings and right nestings) and set partitions avoiding right nestings via an intermediate structure of integer compositions. Such integer compositions are known to be in one-to-one correspondence with self-modified ascent sequences or 31ˉ524ˉ3\bar{1}52\bar{4}-avoiding permutations, as shown by Bousquet-M\'elou, Claesson, Dukes and Kitaev.

Keywords

Cite

@article{arxiv.1009.4535,
  title  = {Partitions and Partial Matchings Avoiding Neighbor Patterns},
  author = {William Y. C. Chen and Neil J. Y. Fan and Alina F. Y. Zhao},
  journal= {arXiv preprint arXiv:1009.4535},
  year   = {2010}
}

Comments

15 pages, 8 figures

R2 v1 2026-06-21T16:17:57.951Z