The diameter of cyclic Kautz digraphs

We present a new kind of digraphs, called cyclic Kautz digraphs CK(d, ɭ), which are subdigraphs of the well-known Kautz digraphs K(d,ɭ). The latter have the smallest diameter among all digraphs with their number of vertices and degree. Cyclic Kautz digraphs CK(d, ɭ) have vertices labeled by all poss...

Full description

Bibliographic Details
Authors: Böhmová, Katerina, Dalfó, Cristina, Huemer, Clemens
Format: article
Status:Versión aceptada para publicación
Publication Date:2017
Country:España
Institution:Universitat de Lleida (UdL)
Repository:Repositori Obert UdL
OAI Identifier:oai:repositori.udl.cat:10459.1/66757
Online Access:https://doi.org/10.2298/FIL1720551B
http://hdl.handle.net/10459.1/66757
Access Level:Open access
Keyword:Digraph
Diameter
Kautz digraph
Description
Summary:We present a new kind of digraphs, called cyclic Kautz digraphs CK(d, ɭ), which are subdigraphs of the well-known Kautz digraphs K(d,ɭ). The latter have the smallest diameter among all digraphs with their number of vertices and degree. Cyclic Kautz digraphs CK(d, ɭ) have vertices labeled by all possible sequences a1 . . . aɭ of length ɭ, such that each character ai is chosen from an alphabet containing d + 1 distinct symbols, where the consecutive characters in the sequence are different (as in Kautz digraphs), and now also requiring that a1 ≠ aɭ. Their arcs are between vertices a1a2 . . . aɭ and a2 . . . aɭ aɭ + 1, with a1 ≠ aɭ and a2 ≠ aɭ + 1. We give the diameter of CK(d, ɭ) for all the values of d and ɭ, and also its number of vertices and arcs.