Signed graphs with totally disconnected star complements
نویسندگان
چکیده
منابع مشابه
Star complements and exceptional graphs
Let G be a finite graph of order n with an eigenvalue μ of multiplicity k. (Thus the μ-eigenspace of a (0, 1)-adjacency matrix of G has dimension k.) A star complement for μ in G is an induced subgraph G−X of G such that |X| = k and G−X does not have μ as an eigenvalue. An exceptional graph is a connected graph, other than a generalized line graph, whose eigenvalues lie in [−2,∞). We establish ...
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We take G to be an undirected graph without loops or multiple edges, with vertex set V (G) = f1; : : : ; ng, and with (0; 1)-adjacency matrix A. Let P denote the orthogonal projection of IR onto the eigenspace E( ) of A, and let fe1; : : : ; eng be the standard orthonormal basis of IR. Since E( ) is spanned by the vectors Pej (j = 1; : : : ; n) there exists X V (G) such that the vectors Pej (j ...
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ژورنال
عنوان ژورنال: Revista de la Unión Matemática Argentina
سال: 2021
ISSN: 1669-9637
DOI: 10.33044/revuma.1480