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arXiv · 0704.2650

Proper path-factors and interval edge-coloring of (3,4)-biregular bigraphs

Armen S. Asratian·Carl Johan Casselgren·Jennifer Vandenbussche·Douglas B. West
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Abstract

An interval coloring of a graph G is a proper coloring of E(G) by positive integers such that the colors on the edges incident to any vertex are consecutive. A (3,4)-biregular bigraph is a bipartite graph in which each vertex of one part has degree 3 and each vertex of the other has degree 4; it is unknown whether these all have interval colorings. We prove that G has an interval coloring using 6 colors when G is a (3,4)-biregular bigraph having a spanning subgraph whose components are paths with endpoints at 3-valent vertices and lengths in {2,4,6,8}. We provide sufficient conditions for the existence of such a subgraph.

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Armen S. Asratian, Carl Johan Casselgren, Jennifer Vandenbussche, Douglas B. West. 2007-04-20. Proper path-factors and interval edge-coloring of (3,4)-biregular bigraphs. https://arxiv.org/abs/0704.2650

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