Destroying symmetry by orienting edges: Complete graphs and complete bigraphs

نویسندگان

  • Frank Harary
  • Michael S. Jacobson
چکیده

Our purpose is to introduce the concept of determining the smallest number of edges of a graph which can be oriented so that the resulting mixed graph has the trivial automorphism group. We find that this number for complete graphs is related to the number of identity oriented trees. For complete bipartite graphs Ks,t, s ≤ t, this number does not always exist. We determine for s ≤ 4 the values of t for which this number does exist.

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عنوان ژورنال:
  • Discussiones Mathematicae Graph Theory

دوره 21  شماره 

صفحات  -

تاریخ انتشار 2001