ArticleOriginal scientific text
Title
Destroying symmetry by orienting edges: complete graphs and complete bigraphs
Authors 1, 2
Affiliations
- Department of Computer Science, New Mexico State University, Las Cruces, NM 88003, USA
- Department of Mathematics, University of Louisville, Louisville, KY 40292, USA
Abstract
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 , s ≤ t, this number does not always exist. We determine for s ≤ 4 the values of t for which this number does exist.
Keywords
oriented graph, automorphism group
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