Nordhaus-gaddum-type Relations for the Energy and Laplacian Energy of Graphs

نویسندگان

  • B. ZHOU
  • I. GUTMAN
چکیده

A b s t r a c t. Let G denote the complement of the graph G . If I(G) is some invariant of G , then relations (identities, bounds, and similar) pertaining to I(G) + I(G) are said to be of Nordhaus-Gaddum type. A number of lower and upper bounds of Nordhaus-Gaddum type are obtained for the energy and Laplacian energy of graphs. Also some new relations for the Laplacian graph energy are established.

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تاریخ انتشار 2007