On mixed radial Moore graphs of diameter 3

Radial Moore graphs and digraphs are extremal graphs related to the Moore ones where the distance-preserving spanning tree is preserved for some vertices. This leads to classify them according to their proximity to being a Moore graph or digraph. In this paper we deal with mixed radial Moore graphs,...

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Detalles Bibliográficos
Autores: Ceresuela, Jesús M., López Lorenzo, Ignacio, Chemisana Villegas, Daniel
Tipo de recurso: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2023
País:España
Institución:Universitat de Lleida (UdL)
Repositorio:Repositori Obert UdL
OAI Identifier:oai:repositori.udl.cat:10459.1/463467
Acceso en línea:https://doi.org/10.1016/j.disc.2023.113525
https://hdl.handle.net/10459.1/463467
Access Level:acceso abierto
Palabra clave:Mixed graph
Degree/diameter problem
Moore bound
Diameter
Descripción
Sumario:Radial Moore graphs and digraphs are extremal graphs related to the Moore ones where the distance-preserving spanning tree is preserved for some vertices. This leads to classify them according to their proximity to being a Moore graph or digraph. In this paper we deal with mixed radial Moore graphs, where the mixed setting allows edges and arcs as different elements. An exhaustive computer search shows the top ranked graphs for an specific set of parameters. Moreover, we study the problem of their existence by providing two infinite families for different values of the degrees and diameter 3. One of these families turns out to be optimal.