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arXiv 2211.05930math.COcs.DM
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II类图分解为两个I类图

Decomposition of class II graphs into two class I graphs

Yan Cao, Guangming Jing, Rong Luo, Vahan Mkrtchyan, Cun-Quan Zhang, Yue Zhao

摘要:

Mkrtchyan和Steffen [J. Graph Theory,70(4),473- 482,2012]证明了每个II类简单图都可以分解为最大$Δ$ -边可着色子图和匹配。他们进一步证明了每一个具有色指数$Δ(G)+k$($k\geq 1$)的图$G$都可以分解为一个最大$Δ(G)$ -边可着色子图(不一定是I类)和一个$k$ -边可着色子图.本文首先将他们的结果推广到多重图,证明了每一个具有重数$μ$的多重图$G$都可以分解为一个最大$Δ(G)$ -边可着色子图和一个最大度至多为$μ$的子图.然后证明了每一个具有色指数$Δ(G)+k$的图$G$都可以分解为两个I类子图$H_1$和$H_2$,使得$Δ(H_1) = Δ(G)$和$Δ(H_2) = k$,这是他们猜想的一个变化.

英文摘要:

Mkrtchyan and Steffen [J. Graph Theory, 70 (4), 473--482, 2012] showed that every class II simple graph can be decomposed into a maximum $Δ$-edge-colorable subgraph and a matching. They further conjectured that every graph $G$ with chromatic index $Δ(G)+k$ ($k\geq 1$) can be decomposed into a maximum $Δ(G)$-edge-colorable subgraph (not necessarily class I) and a $k$-edge-colorable subgraph. In this paper, we first generalize their result to multigraphs and show that every multigraph $G$ with multiplicity $μ$ can be decomposed into a maximum $Δ(G)$-edge-colorable subgraph and a subgraph with maximum degree at most $μ$. Then we prove that every graph $G$ with chromatic index $Δ(G)+k$ can be decomposed into two class I subgraphs $H_1$ and $H_2$ such that $Δ(H_1) = Δ(G)$ and $Δ(H_2) = k$, which is a variation of their conjecture.

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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