More Equienergetic Signed Graphs

Document Type : Special Issue: Energy of Graphs

Authors

Department of Mathematics, Karnatak University, Dharwad - 580003, India

Abstract

The energy of signed graph is the sum of the absolute values of the eigenvalues of its adjacency matrix. Two signed graphs are said to be equienergetic if they have same energy. In the literature the construction of equienergetic signed graphs are reported. In this paper we obtain the characteristic polynomial and energy of the join of two signed graphs and thereby we give another construction of unbalanced, noncospectral equieneregtic signed graphs on n ≥ 8 vertices.

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