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arXiv · 2611.09416

A 4-regular graph with 4/5 of its vertices satisfying the Šoltés property

A. A. Dobrynin
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Abstract

The Wiener index $W(G)$ of a connected graph $G$ is the sum of distances between all unordered pairs of its vertices. A vertex $v$ is called a Šoltés vertex if $G-v$ is connected and $W(G-v)=W(G)$. Since the cycle $C_{11}$ is the only known graph in which every vertex is a Šoltés vertex, a natural problem is to construct other graphs with as large a proportion of such vertices as possible. We construct a $4$-regular graph with Šoltés fraction $4/5$, improving the previous value of $2/3$.

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A. A. Dobrynin. 2026-11-06. A 4-regular graph with 4/5 of its vertices satisfying the Šoltés property. https://arxiv.org/abs/2611.09416

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