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dc.contributor.authorDalfó, Cristina
dc.contributor.authorFiol, Miguel Angel
dc.contributor.authorKoolen, Jack
dc.date.accessioned2019-11-11T11:45:09Z
dc.date.available2019-11-11T11:45:09Z
dc.date.issued2018-07-13
dc.identifier.issn0308-1087
dc.identifier.urihttp://hdl.handle.net/10459.1/67511
dc.description.abstractWe study regular graphs whose distance-2 graph or distance-1-or-2 graph is strongly regular. We provide a characterization of such graphs Γ (among regular graphs with few distinct eigenvalues) in terms of the spectrum and the mean number of vertices at maximal distance d from every vertex, where d+1 is the number of different eigenvalues of Γ. This can be seen as another version of the so-called spectral excess theorem, which characterizes in a similar way those regular graphs that are distance-regular.
dc.description.sponsorshipResearch of C. Dalfó and M. A. Fiol is partially supported by Agència de Gestió d'Ajuts Universitaris i de Recerca (AGAUR) under project 2017SGR1087. Research of J. Koolen is partially supported by the National Natural Science Foundation of China under project No. 11471009, and the Chinese Academy of Sciences under its ‘100 talent’ programme. The research of C. Dalfó has also received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 734922.
dc.format.mimetypeapplication/pdf
dc.language.isoeng
dc.publisherTaylor & Francis
dc.relation.isformatofVersió postprint del document publicat a: https://doi.org/10.1080/03081087.2018.1491944
dc.relation.ispartofLinear & Multilinear Algebra, 2019, vol. 67, num. 12, p. 2373-2381
dc.rights(c) Taylor & Francis, 2019
dc.subjectDistance-regular graph
dc.subjectDistance-2 graph
dc.subjectSpectrum
dc.subjectPredistance polynomials
dc.titleThe spectral excess theorem for graphs with few eigenvalues whose distance- 2 or distance-1-or-2 graph is strongly regular
dc.typeinfo:eu-repo/semantics/article
dc.date.updated2019-11-11T11:45:09Z
dc.identifier.idgrec027997
dc.type.versioninfo:eu-repo/semantics/acceptedVersion
dc.rights.accessRightsinfo:eu-repo/semantics/openAccess
dc.identifier.doihttps://doi.org/10.1080/03081087.2018.1491944
dc.relation.projectIDinfo:eu-repo/grantAgreement/EC/H2020/734922/EU/CONNECT


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