Circular-Perfect Concave-Round Graphs

  • Sylvain Coulonges
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4271)


For 1≤dkd, K k/d denotes the graph with vertices 0,1,...,k–1, in which i is adjacent to j if and only if d≤|ij|≤kd. A graph G is circular-perfect if, for every induced subgraph H of G, the infinum k/d for which H admits a homomorphism to K k/d is equal to the supremum k/d for which K k/d admits a homomorphism to H. We answer a question af Bang-Jensen and Huang by giving a complete characterization of circular-perfect concave-round graphs.


Chromatic Number Complete Characterization Perfect Graph Clique Size Circular Coloring 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Sylvain Coulonges
    • 1
  1. 1.Laboratoire Bordelais de Recherche Informatique (LaBRI) TalenceFrance

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