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arXiv 1502.06168math.COcs.DMcs.DS
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团覆盖数的一个新的上界及其应用

A new upper bound for the clique cover number with applications

Farhad Shahrokhi

摘要:

设$α(G)$和$β(G)$表示无向图$G$的最大独立集的大小和团覆盖数。设$H$是一个具有$V(G)=V(H)$和$E(G)\subseteq E(H)$的区间图,$ϕ(G,H)$表示$G$的${β(G[W])\over α(G[W])}$整体导出子图$G[W]$的最大值,这些子图是$H$中的团.本文的主要结果是证明了对任何图$G$ $${β(G)}\le 2 α(H)ϕ(G,H)(\log α(H)+1),$$,其中$α(H)$是$H$中最大独立集的大小。我们进一步提供了一个推广,显着统一或改善过去的一些算法和结构的结果,一些著名的交叉图的团覆盖数。

英文摘要:

Let $α(G)$ and $β(G)$, denote the size of a largest independent set and the clique cover number of an undirected graph $G$. Let $H$ be an interval graph with $V(G)=V(H)$ and $E(G)\subseteq E(H)$, and let $ϕ(G,H)$ denote the maximum of ${β(G[W])\over α(G[W])}$ overall induced subgraphs $G[W]$ of $G$ that are cliques in $H$. The main result of this paper is to prove that for any graph $G$ $${β(G)}\le 2 α(H)ϕ(G,H)(\log α(H)+1),$$ where, $α(H)$ is the size of a largest independent set in $H$. We further provide a generalization that significantly unifies or improves some past algorithmic and structural results concerning the clique cover number for some well known intersection graphs.

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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