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 


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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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