Corpus ID: 85499123

Good orientations of 2T-graphs

  title={Good orientations of 2T-graphs},
  author={J. Bang-Jensen and S. Bessy and J. Huang and M. Kriesell},
  journal={arXiv: Combinatorics},
In this paper we study graphs which admit acyclic orientations that contain a pair of arc-disjoint out-branching and in-branching (such an orientation is called good) and we focus on edge-minimal such graphs. A 2T-graph is a graph whose edge set can be decomposed into two edge-disjoint spanning trees. Vertex-minimal 2T-graphs with at least two vertices which are known as generic circuits play an important role in rigidity theory for graphs. We prove that every generic circuit has a good… Expand

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  • J. Bang-Jensen
  • Computer Science, Mathematics
  • J. Comb. Theory, Ser. B
  • 1991
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