Journal of Heuristics

, Volume 10, Issue 4, pp 407–413 | Cite as

New Results on the Queens_n2 Graph Coloring Problem

  • Michel Vasquez


For the Queens_n2 graph coloring problems no chromatic numbers are available for n > 9 except where n is not a multiple of 2 or 3. In this paper we propose an exact algorithm that takes advantage of the particular structure of these graphs. The algorithm works on the independent sets of the graph rather than on the vertices to be colored. It combines branch and bound, for independent set assignment, with a clique based filtering procedure. A first experimentation of this approach provided the coloring number values ranging for n = 10 to n = 14.

queens graphs graph coloring independent sets cliques based filtering 


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Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • Michel Vasquez
    • 1
  1. 1.URC-EMA-CEALGI2P Research Center30035 Nîmes Cedex 1France

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