dc.contributor
Universitat Politècnica de Catalunya. Departament de Ciències de la Computació
dc.contributor.author
López Lorenzo, Nacho
dc.contributor.author
Messegué Buisan, Arnau
dc.contributor.author
Miret Biosca, Josep Maria
dc.date.issued
2023-03-24
dc.identifier
López, N.; Messegue, A.; Miret, J. Nonexistence of almost Moore digraphs of degrees 4 and 5 with self-repeats. "Electronic journal of combinatorics", 24 Març 2023, vol. 30, núm. 1, article P1.56, p. 1-15.
dc.identifier
https://hdl.handle.net/2117/386781
dc.identifier
10.37236/11335
dc.description.abstract
An almost Moore (d,k)-digraph is a regular digraph of degree d>1, diameter k>1 and order N(d,k)=d+d2+⋯+dk. So far, their existence has only been shown for k=2, whilst it is known that there are no such digraphs for k=3, 4 and for d=2, 3 when k≥3. Furthermore, under certain assumptions, the nonexistence for the remaining cases has also been shown. In this paper, we prove that (4,k) and (5,k)-almost Moore digraphs with self-repeats do not exist for k≥5.
dc.description.abstract
Nacho López: Supported in part by grants PID2020-115442RB-I00 and 2021 SGR-00434.
Arnau Messegué: Supported in part by grants Margarita Sala and 2021SGR-00434.
Josep M. Miret: Supported in part by grants PID2021-124613OB-I00 and 2021 SGR-00434.
dc.description.abstract
Peer Reviewed
dc.description.abstract
Postprint (published version)
dc.format
application/pdf
dc.relation
https://www.combinatorics.org/ojs/index.php/eljc/article/view/v30i1p56
dc.rights
http://creativecommons.org/licenses/by-nd/4.0/
dc.rights
Attribution-NoDerivatives 4.0 International
dc.subject
Àrees temàtiques de la UPC::Informàtica::Informàtica teòrica
dc.subject
Àrees temàtiques de la UPC::Matemàtiques i estadística::Matemàtica discreta::Teoria de grafs
dc.subject
Directed graphs
dc.subject
Grafs dirigits
dc.title
Nonexistence of almost Moore digraphs of degrees 4 and 5 with self-repeats
