An improved upper bound for the order of mixed graphs

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2018Suggested citation
Dalfó, Cristina;
Fiol, Miguel Angel;
López Lorenzo, Ignacio;
.
(2018)
.
An improved upper bound for the order of mixed graphs.
Discrete mathematics, october 2018, vol. 341, núm. 10, p. 2872-2877.
https://doi.org/10.1016/j.disc.2018.06.016.
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A mixed graph G can contain both (undirected) edges and arcs (directed edges). Here we derive an improved Moore-like bound for the maximum number of vertices of a mixed graph with diameter at least three. Moreover, a complete enumeration of all optimal (1; 1)-regular mixed graphs with diameter three is presented, so proving that, in general, the proposed bound cannot be improved.
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Discrete mathematics, october 2018, vol. 341, núm. 10, p. 2872-2877European research projects
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