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arXiv · 1107.4879

On strongly spanning $k$-edge-colorable subgraphs

Vahan V. Mkrtchyan·Gagik N. Vardanyan
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Abstract

A subgraph $H$ of a multigraph $G$ is called strongly spanning, if any vertex of $G$ is not isolated in $H$, while it is called maximum $k$-edge-colorable, if $H$ is proper $k$-edge-colorable and has the largest size. We introduce a graph-parameter $sp(G)$, that coincides with the smallest $k$ that a graph $G$ has a strongly spanning maximum $k$-edge-colorable subgraph. Our first result offers some alternative definitions of $sp(G)$. Next, we show that $\Delta(G)$ is an upper bound for $sp(G)$, and then we characterize the class of graphs $G$ that satisfy $sp(G)=\Delta(G)$. Finally, we prove some bounds for $sp(G)$ that involve well-known graph-theoretic parameters.

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Vahan V. Mkrtchyan, Gagik N. Vardanyan. 2011-07-25. On strongly spanning $k$-edge-colorable subgraphs. https://arxiv.org/abs/1107.4879

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