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

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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

Abstract

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.

References

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