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arXiv 2610.19014math.CO
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5-正则图与8-正则图的内部划分

Internal partitions of $5$-regular and $8$-regular graphs

Center for Discrete Mathematics, Fuzhou University(福州大学离散数学中心)

Siwei Lin, Qinghou Zeng

AI总结:

本文证实了DeVos提出的关于r-正则图内部划分的问题,证明顶点数≥10^7的5-正则图和8-正则图均存在内部划分,补充了此前仅r∈{3,4,6}成立的结论。

摘要:

图的内部划分是将其顶点集划分为两个非空部分,使得每个顶点至少有一半的邻居在自身部分内。DeVos提出问题:对于每个固定正整数r,是否除有限个外的所有r-正则图都存在内部划分。此前仅已知r∈{3,4,6}时成立,本文针对r∈{5,8}证实该结论,证明每个顶点数至少为10^7的r-正则图都存在内部划分。

英文摘要:

An \emph{internal partition} of a graph is a partition of its vertex set into two nonempty parts such that every vertex has at least half of its neighbors in its own part. DeVos asked whether, for every fixed positive integer $r$, all but finitely many $r$-regular graphs admit an internal partition. This was previously known to hold only for $r\in\{3,4,6\}$. In this paper, we confirm this for $r\in\{5,8\}$ by proving that every $r$-regular graph on at least $10^7$ vertices has an internal partition.

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。

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