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arXiv · 2402.15778

Graphs with a given conditional diameter that maximize the Wiener index

Junfeng An·Yingzhi Tian
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Abstract

The Wiener index $W(G)$ of a graph $G$ is one of the most well-known topological indices, which is defined as the sum of distances between all pairs of vertices of $G$. The diameter $D(G)$ of $G$ is the maximum distance between all pairs of vertices of $G$; the conditional diameter $D(G;s)$ is the maximum distance between all pairs of vertex subsets with cardinality $s$ of $G$. When $s=1$, the conditional diameter $D(G;s)$ is just the diameter $D(G)$. The authors in \cite{QS} characterized the graphs with the maximum Wiener index among all graphs with diameter $D(G)=n-c$, where $1\le c\le 4$. In this paper, we will characterize the graphs with the maximum Wiener index among all graphs with conditional diameter $D(G;s)=n-2s-c$ ( $-1\leq c\leq 1$), which extends partial results in \cite{QS}.

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Junfeng An, Yingzhi Tian. 2024-02-24. Graphs with a given conditional diameter that maximize the Wiener index. https://arxiv.org/abs/2402.15778

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