Restricted single or double signed patterns
组合数学
2007-05-23 v1
摘要
Let be the set of all signed permutations on the symbols 1,2,...,n with signs 1,2,...,r. We prove, for every 2-letter signed pattern , that the number of -avoiding signed permutations in is given by the formula . Also we prove that there are only one Wilf class for r=1, four Wilf classes for r=2, and six Wilf classes for .
引用
@article{arxiv.math/0011072,
title = {Restricted single or double signed patterns},
author = {T. Mansour},
journal= {arXiv preprint arXiv:math/0011072},
year = {2007}
}
备注
13 pages, 1 table, 1 figure