ISSN 1234-3099 (print version)

ISSN 2083-5892 (electronic version)

Discussiones Mathematicae Graph Theory

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Discussiones Mathematicae Graph Theory


Discussiones Mathematicae Graph Theory 32(2) (2012) 255-261
DOI: 10.7151/dmgt.1612

The Laplacian Spectrum of Some Digraphs Obtained from the Wheel

Li Su, Hong-Hai Li and Liu-Rong Zheng

College of Mathematics and Information Science
Jiangxi Normal University
Nanchang, 330022, P.R. China


The problem of distinguishing, in terms of graph topology, digraphs with real and partially non-real Laplacian spectra is important for applications. Motivated by the question posed in [R. Agaev, P. Chebotarev, Which digraphs with rings structure are essentially cyclic?, Adv. in Appl. Math. 45 (2010), 232-251], in this paper we completely list the Laplacian eigenvalues of some digraphs obtained from the wheel digraph by deleting some arcs.

Keywords: digraph, Laplacian matrix, eigenvalue, wheel

2010 Mathematics Subject Classification: 05C50, 15A18.


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Received 10 February 2011
Revised 10 May 2011
Accepted 10 May 2011