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A note on non-repetitive colourings of planar graphs

Narad Rampersad
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Abstract

Alon et al. introduced the concept of non-repetitive colourings of graphs. Here we address some questions regarding non-repetitive colourings of planar graphs. Specifically, we show that the faces of any outerplanar map can be non-repetitively coloured using at most five colours. We also give some lower bounds for the number of colours required to non-repetitively colour the vertices of both outerplanar and planar graphs.

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Narad Rampersad. 2003-07-28. A note on non-repetitive colourings of planar graphs. https://arxiv.org/abs/math/0307365

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