English

Statistics of Partial Permutations via Catalan matrices

Combinatorics 2022-07-22 v1

Abstract

A generalized Catalan matrix (an,k)n,k0(a_{n,k})_{n,k\ge 0} is generated by two seed sequences s=(s0,s1,)\mathbf{s}=(s_0,s_1,\ldots) and t=(t1,t2,)\mathbf{t}=(t_1,t_2,\ldots) together with a recurrence relation. By taking s=2+1s_\ell=2\ell+1 and t=2t_\ell=\ell^2 we can interpret an,ka_{n,k} as the number of partial permutations, which are n×nn\times n 0,10,1-matrices of kk zero rows with at most one 11 in each row or column. In this paper we prove that most of fundamental statistics and some set-valued statistics on permutations can also be defined on partial permutations and be encoded in the seed sequences. Results on two interesting permutation families, namely the connected permutations and cycle-up-down permutations, are also given.

Keywords

Cite

@article{arxiv.2207.10252,
  title  = {Statistics of Partial Permutations via Catalan matrices},
  author = {Yen-Jen Cheng and Sen-Peng Eu and Hsiang-Chun Hsu},
  journal= {arXiv preprint arXiv:2207.10252},
  year   = {2022}
}

Comments

22 pages

R2 v1 2026-06-25T01:06:04.432Z