Abstract
An oriented graph is a digraph with no symmetric pairs of directed arcs and without loops. The score of a vertexv i in an oriented graph D is\(a_{v_i } \) (or simply ai)\(d_{v_i }^ - \) are the outdegree and indegree, respectively, ofv i and n is the number of vertices in D. In this paper, we give a new proof of Avery’s theorem and obtain some stronger inequalities for scores in oriented graphs. We also characterize strongly transitive oriented graphs.
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Pirzada, S., Naikoo, T.A. & Shah, N.A. Score sequences in oriented graphs. J. Appl. Math. Comput. 23, 257–268 (2007). https://doi.org/10.1007/BF02831973
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DOI: https://doi.org/10.1007/BF02831973