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arXiv · 2504.13695

Perfect weighted divisibility is equivalent to perfect divisibility

Qiming Hu·Baogang Xu·Miaoxia Zhuang
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Abstract

A graph is perfectly divisible if for each of its induced subgraph $H$, $V(H)$ can be partitioned into $A$ and $B$ such that $H[A]$ is perfect and $\omega(H[B]) < \omega(H)$. A graph $G$ is perfectly weight divisible if for every positive integral weight function on $V(G)$ and each of its induced subgraph $H$, $V(H)$ can be partitioned into $A$ and $B$ such that $H[A]$ is perfect and the maximum weight of a clique in $H[B]$ is smaller than the maximum weight of a clique in $H$. In this paper, we prove that the perfect divisibility of a graph is equivalent to its perfect weighted divisibility.

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Qiming Hu, Baogang Xu, Miaoxia Zhuang. 2025-04-18. Perfect weighted divisibility is equivalent to perfect divisibility. https://arxiv.org/abs/2504.13695

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