Unicyclic graphs with maximal energy
نویسندگان
چکیده
Let G be a graph on n vertices and let λ1, λ2, . . . , λn be its eigenvalues. The energy of G is defined as E(G) = |λ1| + |λ2| + · · · + |λn|. For various classes of unicyclic graphs, the graphs with maximal energy are determined. Let P 6 n be obtained by connecting a vertex of the circuit C6 with a terminal vertex of the path Pn−6. For n 7, P 6 n has the maximal energy among all connected unicyclic bipartite n-vertex graphs, except the circuit Cn. © 2002 Elsevier Science Inc. All rights reserved. AMS classification: 05C35; 05C50; 05C90
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