DEGREE SUM SPECTRA AND DEGREE SUM ENERGY OF CERTAIN FAMILIES OF GRAPHS

Year 2025, Volume: 15 Issue: 9, 2284 - 2296, 01.09.2025

Keerthi G. Mirajkar Roopa S. Naikar Parvathalu Bparvat

Abstract

For any simple graph G, the degree sum matrix is defined as a matrix in which each entry represents the sum of the degrees of a pair of vertices. The degree sum energy is the absolute sum of the eigenvalues of the degree sum matrix of G. In this paper, we determine the degree sum spectra and the degree sum energy of certain classes of graphs and their complements.

Keywords

Degree sum spectra , degree sum energy , sunlet graph , windmill graph , complement of a graph

Thanks

The authors are grateful to the referees for their valuable comments, which have improved the presentation of the paper. The author R. S. Naikar is thankful to Karnataka Science and Technology Promotion Society, Bengalore, India for providing Ph. D. fellowship.

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