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arXiv · 1610.07177

Colouring of (P3UP2)-free graphs

Arpitha P. Bharathi·Sheshayya A. Choudum
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Abstract

The class of 2K2-free graphs and its various subclasses have been studied in a variety of contexts. In this paper, we are concerned with the colouring of (P3UP2)-free graphs, a super class of 2K2-free graphs. We derive a O(w^3) upper bound for the chromatic number of (P3UP2)-free graphs, and sharper bounds for (P3UP2), diamond)-free graphs, where w denotes the clique number. By applying similar proof techniques we obtain chromatic bounds for (2K2, diamond)-free graphs. The last two classes are perfect if w >=5 and >= 4 respectively.

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Arpitha P. Bharathi, Sheshayya A. Choudum. 2016-10-23. Colouring of (P3UP2)-free graphs. https://doi.org/10.1007/s00373-017-1870-8

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