Restricted non-separable planar maps and some pattern avoiding permutations
Abstract
Tutte founded the theory of enumeration of planar maps in a series of papers in the 1960s. Rooted non-separable planar maps are in bijection with West-2-stack-sortable permutations, beta(1,0)-trees introduced by Cori, Jacquard and Schaeffer in 1997, as well as a family of permutations defined by the avoidance of two four letter patterns. In this paper we give upper and lower bounds on the number of multiple-edge-free rooted non-separable planar maps. We also use the bijection between rooted non-separable planar maps and a certain class of permutations, found by Claesson, Kitaev and Steingrimsson in 2009, to show that the number of 2-faces (excluding the root-face) in a map equals the number of occurrences of a certain mesh pattern in the permutations. We further show that this number is also the number of nodes in the corresponding beta(1,0)-tree that are single children with maximum label. Finally, we give asymptotics for some of our enumerative results.
Cite
@article{arxiv.1202.1790,
title = {Restricted non-separable planar maps and some pattern avoiding permutations},
author = {Sergey Kitaev and Pavel Salimov and Christopher Severs and Henning Ulfarsson},
journal= {arXiv preprint arXiv:1202.1790},
year = {2012}
}
Comments
18 pages, 14 figures