Coloured permutations containing and avoiding certain patterns
Combinatorics
2007-05-23 v1
Abstract
Following Mansour, let be the set of all coloured permutations on the symbols with colours , which is the analogous of the symmetric group when r=1, and the hyperoctahedral group when r=2. Let be subset of d colours; we define be the set of all coloured permutations such that where . We prove that, the number -avoiding coloured permutations in equals for where . We then prove that for any (or any ), the number of coloured permutations in which avoid all patterns in (or in ) except for and contain exactly once equals for . Finally, for any , , this number equals for . These results generalize recent results due to Mansour, and due to Simion.
Cite
@article{arxiv.math/0112018,
title = {Coloured permutations containing and avoiding certain patterns},
author = {T. Mansour},
journal= {arXiv preprint arXiv:math/0112018},
year = {2007}
}
Comments
7 pages