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arXiv · 2106.06864

On the Refinement of Certain Statistics on Alternating Words

Chia-An Hsu·Hsu-Lin Chien·Han-Chun Chan·Bin-Shun Sun·Yuan-Ting Huang
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Abstract

In this paper, we investigate statistics on alternating words under correspondence between ``possible reflection paths within several layers of glass'' and ``alternating words''. For $v=(v_1,v_2,\cdots,v_n)\in\mathbb{Z}^{n}$, we say $P$ is a path within $n$ glass plates corresponding to $v$, if $P$ has exactly $v_i$ reflections occurring at the $i^{\rm{th}}$ plate for all $i\in\{1,2,\cdots,n\}$. We give a recursion for the number of paths corresponding to $v$ satisfying $v \in \mathbb{Z}^n$ and $\sum_{i\geq 1} v_i=m$. Also, we establish recursions for statistics around the number of paths corresponding to a given vector $v\in\mathbb{Z}^n$ and a closed form for $n=3$. Finally, we give a equivalent condition for the existence of path corresponding to a given vector $v$.

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Chia-An Hsu, Hsu-Lin Chien, Han-Chun Chan, Bin-Shun Sun, Yuan-Ting Huang. 2021-06-12. On the Refinement of Certain Statistics on Alternating Words. https://arxiv.org/abs/2106.06864

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