arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2103.00246math.CO
收藏

一种避免纽模式1-32-4的置换的单标号生成树

A generating tree with a single label for permutations avoiding the vincular pattern 1-32-4

Matteo Cervetti

摘要:

在本文中,我们继续研究的置换,避免了长春模式$1-32-4$通过构建一个生成树与一个单一的标签,这些置换。这个结构最后提供了一个更清楚的解释,为什么卡兰发现的某个递归公式实际上计算了这些排列,因为这个公式最初只是作为一个非常复杂的双射与某类有序有根树的结果而获得的。这回应了Duchi、Guerrini和Rinaldi已经提出的一个理论问题。作为一个副产品,我们还获得了一个算法来生成所有这些排列,我们根据一个简单的统计来细化它们的枚举,这个统计是1右边从右到左的最大值的数量。

英文摘要:

In this paper we continue the study of permutations avoiding the vincular pattern $1-32-4$ by constructing a generating tree with a single label for these permutations. This construction finally provides a clearer explanation of why a certain recursive formula found by Callan actually counts these permutations, insofar as this formula was originally obtained only as a consequence of a very intricated bijection with a certain class of ordered rooted trees. This responds to a theoretical issue already raised by Duchi, Guerrini and Rinaldi. As a byproduct, we also obtain an algorithm to generate all these permutations and we refine their enumeration according to a simple statistic, which is the number of right-to-left maxima to the right of 1.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑