Total-Chromatic Number and Chromatic Index of Dually Chordal Graphs

نویسندگان

  • Celina M. H. de Figueiredo
  • João Meidanis
  • Célia Picinin de Mello
چکیده

A graph is dually chordal if it is the clique graph of a chordal graph. Alternatively, a graph is dually chordal if it admits a maximum neighbourhood order. This class generalizes known subclasses of chordal graphs such as doubly chordal graphs, strongly chordal graphs and interval graphs. We prove that Vizing's total-colour conjecture holds for dually chordal graphs. We describe a new heuristic that yields an exact total-colouring algorithm for even maximum degree dually chordal graphs and an exact edge-colouring algorithm for odd maximum degree dually chordal graphs.

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عنوان ژورنال:
  • Inf. Process. Lett.

دوره 70  شماره 

صفحات  -

تاریخ انتشار 1999