{ "id": "1304.3524", "version": "v1", "published": "2013-04-12T02:21:07.000Z", "updated": "2013-04-12T02:21:07.000Z", "title": "Characterization of tricyclic graphs with exactly two $Q$-main eigenvalues", "authors": [ "Shuchao Li", "Xue Yang" ], "comment": "25 pages;6 figures", "categories": [ "math.CO" ], "abstract": "The signless Laplacian matrix of a graph $G$ is defined to be the sum of its adjacency matrix and degree diagonal matrix, and its eigenvalues are called $Q$-eigenvalues of $G$. A $Q$-eigenvalue of a graph $G$ is called a $Q$-main eigenvalue if it has an eigenvector the sum of whose entries is not equal to zero. Chen and Huang [L. Chen, Q.X. Huang, Trees, unicyclic graphs and bicyclic graphs with exactly two $Q$-main eigenvalues, submitted for publication] characterized all trees, unicylic graphs and bicyclic graphs with exactly two main $Q$-eigenvalues, respectively. As a continuance of it, in this paper, all tricyclic graphs with exactly two $Q$-main eigenvalues are characterized.", "revisions": [ { "version": "v1", "updated": "2013-04-12T02:21:07.000Z" } ], "analyses": { "subjects": [ "05C50", "15A18" ], "keywords": [ "main eigenvalue", "tricyclic graphs", "characterization", "bicyclic graphs", "degree diagonal matrix" ], "note": { "typesetting": "TeX", "pages": 25, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013arXiv1304.3524L" } } }