On large regular (1, 1, k)-mixed graphs

An (r,z,k)-mixed graph G has every vertex with undirected degree r, directed in- and out-degree z, and diameter k. In this paper, we study the case r = z = 1, proposing some new constructions of (1,1,k)-mixed graphs with a large number of vertices N. Our study is based on computer techniques for sma...

Descripción completa

Detalles Bibliográficos
Autores: Dalfó, Cristina, Erskine, G., Exoo, G., Fiol Mora, Miguel Ángel, López Lorenzo, Ignacio, Massegué Buisan, Arnau, Tuite, J.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10459.1/466203
Acceso en línea:https://doi.org/10.1016/j.dam.2024.06.001
https://hdl.handle.net/10459.1/466203
Access Level:acceso abierto
Palabra clave:Mixed graph
Moore bound
Cayley graph
Lift graph
Descripción
Sumario:An (r,z,k)-mixed graph G has every vertex with undirected degree r, directed in- and out-degree z, and diameter k. In this paper, we study the case r = z = 1, proposing some new constructions of (1,1,k)-mixed graphs with a large number of vertices N. Our study is based on computer techniques for small values of k and the use of graphs on alphabets for general k. In the former case, the constructions are either Cayley or lift graphs. In the latter case, some infinite families of (1,1,k)-mixed graphs are proposed with diameter of the order of 2log2 N.