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arXiv · 1206.0233

3-Colourability of Dually Chordal Graphs in Linear Time

Arne Leitert
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Abstract

A graph G is dually chordal if there is a spanning tree T of G such that any maximal clique of G induces a subtree in T. This paper investigates the Colourability problem on dually chordal graphs. It will show that it is NP-complete in case of four colours and solvable in linear time with a simple algorithm in case of three colours. In addition, it will be shown that a dually chordal graph is 3-colourable if and only if it is perfect and has no clique of size four.

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Arne Leitert. 2012-11-13. 3-Colourability of Dually Chordal Graphs in Linear Time. https://arxiv.org/abs/1206.0233

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