arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2108.08299math.CO
收藏

山谷序列上的限制Dyck路径

Restricted Dyck Paths on Valleys Sequence

Rigoberto Flórez, Toufik Mansour, José L. Ramírez, Fabio A. Velandia, Diego Villamizar

摘要:

本文研究了经典格点路径\emph{Dyck paths}的一个子类,称为\emph{restricted $d$-Dyck}路径,简称$d$ -Dyck. Dyck路径$P$的谷是$P$的局部极小值;如果两个连续谷的高度差(从左至右)至少为$d$,我们说$P$是一条受限的$d$路径。Dyck路径的\emph{area}是$y$的绝对值之和。我们发现的峰值的数量和面积的所有路径的给定长度的集合中的$d$ -Dyck路径。我们给出了一个二元生成函数来计算$d$ -Dyck路径的个数与半长和峰数的关系。在此基础上,详细分析了案例$d=-1$。除其他事项外,我们给两者,生成函数和递归关系的总面积。

英文摘要:

In this paper we study a subfamily of a classic lattice path, the \emph{Dyck paths}, called \emph{restricted $d$-Dyck} paths, in short $d$-Dyck. A valley of a Dyck path $P$ is a local minimum of $P$; if the difference between the heights of two consecutive valleys (from left to right) is at least $d$, we say that $P$ is a restricted $d$-Dyck path. The \emph{area} of a Dyck path is the sum of the absolute values of $y$-components of all points in the path. We find the number of peaks and the area of all paths of a given length in the set of $d$-Dyck paths. We give a bivariate generating function to count the number of the $d$-Dyck paths with respect to the the semi-length and number of peaks. After that, we analyze in detail the case $d=-1$. Among other things, we give both, the generating function and a recursive relation for the total area.

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。

↑