On transitive orientations of G-e

نویسنده

  • Michael Andresen
چکیده

A comparability graph is a graph whose edges can be oriented transitively. Given a comparability graph G = (V, E) and an arbitrary edge ê ∈ E we explore the question whether the graph G − ê, obtained by removing the undirected edge ê, is a comparability graph as well. We define a new substructure of implication classes and present a complete mathematical characterization of all those edges.

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عنوان ژورنال:
  • Discussiones Mathematicae Graph Theory

دوره 29  شماره 

صفحات  -

تاریخ انتشار 2009