Generalized colorings and avoidable orientations

نویسندگان

  • Jenö Szigeti
  • Zsolt Tuza
چکیده

Gallai and Roy proved that a graph is k-colorable if and only if it has an orientation without directed paths of length k. We initiate the study of analogous characterizations for the existence of generalized graph colorings, where each color class induces a subgraph satisfying a given (hereditary) property. It is shown that a graph is partitionable into at most k independent sets and one induced matching if and only if it admits an orientation containing no subdigraph from a family of k + 3 directed graphs.

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عنوان ژورنال:
  • Discussiones Mathematicae Graph Theory

دوره 17  شماره 

صفحات  -

تاریخ انتشار 1997