Extending precolourings of circular cliques

نویسندگان

  • Richard C. Brewster
  • Jonathan A. Noel
چکیده

Let G be a graph with circular chromatic number χc(G) = k q . Given P ⊆ V (G) where each component of G[P ] is isomorphic to the circular clique Gk,q, suppose the vertices of P have been precoloured with a (k, q)-colouring. We examine under what conditions one can be assured the precolouring extends to the entire graph. We study sufficient conditions based on k ′ q − k q as well as the distance between precoloured components of G[P ]. In particular, we examine a conjecture of Albertson and West showing the conditions for extendibility are more complex than anticipated in their work.

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عنوان ژورنال:
  • Discrete Mathematics

دوره 312  شماره 

صفحات  -

تاریخ انتشار 2012