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arXiv · 1610.00952

On colouring point visibility graphs

Ajit Arvind Diwan·Bodhayan Roy
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Abstract

In this paper we show that it can be decided in polynomial time whether or not the visibility graph of a given point set is 4-colourable, and such a 4-colouring, if it exists, can also be constructed in polynomial time. We show that the problem of deciding whether the visibility graph of a point set is 5-colourable, is NP-complete. We give an example of a point visibility graph that has chromatic number 6 while its clique number is only 4.

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Ajit Arvind Diwan, Bodhayan Roy. 2016-10-04. On colouring point visibility graphs. https://arxiv.org/abs/1610.00952

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