English

Combinatorial bijections from hatted avoiding permutations in $S_n(132)$ to generalized Dyck and Motzkin paths

Combinatorics 2012-08-07 v1

Abstract

We introduce a new concept of permutation avoidance pattern called hatted pattern, which is a natural generalization of the barred pattern. We show the growth rate of the class of permutations avoiding a hatted pattern in comparison to barred pattern. We prove that Dyck paths with no peak at height pp, Dyck paths with no ud...duud... du and Motzkin paths are counted by hatted pattern avoiding permutations in \sn(132)\s_n(132) by showing explicit bijections. As a result, a new direct bijection between Motzkin paths and permutations in \sn(132)\s_n(132) without two consecutive adjacent numbers is given. These permutations are also represented on the Motzkin generating tree based on the Enumerative Combinatorial Object (ECO) method.

Keywords

Cite

@article{arxiv.1208.1075,
  title  = {Combinatorial bijections from hatted avoiding permutations in $S_n(132)$ to generalized Dyck and Motzkin paths},
  author = {Phan Thuan Do and Dominique Rossin and Thi Thu Huong Tran},
  journal= {arXiv preprint arXiv:1208.1075},
  year   = {2012}
}

Comments

19 pages, 9 figures