Vertex Energy of Small Integral Graphs
Vertex Energy of Small Integral Graphs
Abstract
The energy of a graph, introduced in 1970's, is a well studied spectrum based graph invariant that has a notable number of applications in different fields of science. Recently, Arizmendi et al. have reworked on this idea by introducing the concept of vertex energy of a graph which reflects upon the way the total energy is distributed among the individual vertices. Further, they have explained a method of computing the energy of a vertex $v$ by means of solving a system of linear equations involving the number of $v-v$ walks of different lengths from $v$. In the present study, we compute the vertex energies for all non-trivial connected integral graphs of order up to seven using this method.
Downloads
References
\bibitem{bali02} K. Bali$\grave{n}$ska, D. Cvetkovi$\acute{c}$, Z. Radosavljevi$\acute{c}$, S. Simi$\acute{c}$, D. Stevanovi$\acute{c}$, A survey on integral graphs, {\it Publikacije Elektrotehni$\breve{c}$kog fakulteta. Serija Matematika} {\bf 13} (2002) 42-65.
\bibitem{brou12} A. E. Brouwer, W. H. Haemers, Spectra of Graphs, {\it Springer New York}, New York, 2012.
\bibitem{brou08} A. E. Brouwer, Small integral trees,{\it The Electron. J. Comb. } {\bf 15} (2008), \#N1.
\bibitem{gutm78} I. Gutman, The energy of a graph, {\it Ber. Math. Statist. Sekt. Forschungszentrum Graz.} {\bf 103} (1978) 1–22.
\bibitem{gutm25} I. Gutman, B. Furtula, Calculating Vertex Energies of Graphs - A Tutorial, {\it MATCH Commun. Math. Comput. Chem.} {\bf 93(3)} (2025) 691-698.
\bibitem{hara74} F. Harary, A. J. Schwenk, Which graphs have integral spectra?, in: R. Bari and F. Harary (Eds.), {\it Graphs and Combinatorics}, Springer-Verlag, Berlin, 1974, pp. 45-51.
\bibitem{indu07} G. Indulal, A. Vijaykumar, Some new integral graphs, {\it Applicable Analysis and Discrete Mathematics} {\bf 1} (2007) 420–426.
\bibitem{rama25} H. S. Ramane, S. Y. Chowri, T. Shivaprasad, I. Gutman, Energy of Vertices of Subdivision Graphs, {\it MATCH Commun. Math. Comput. Chem.} {\bf 93(3)} (2025) 701-711.
\bibitem{nara25} H. T. Sharathkumar, C. K. Shrikanth, N. Narahari, H. M. Nagesh, U. Vijay Chandra Kumar, On the vertex energy of small integral trees, {\it MATCH Commun. Math. Comput. Chem.} (\emph{(in press)}.
\bibitem{sloa} N. J. A. Sloane, Sequences 064731 A and A077027 in "The On-Line Encyclopedia of Integer Sequences.", https://oeis.org/A064731
\bibitem{wang05} L. Wang, A survey of results on integral trees and integral graphs, University of Twente, The Netherlands, 2005.
\bibitem{web} E. W. Weisstein, "Integral Graph." From MathWorld--A Wolfram Web Resource, https://mathworld.wolfram.com/IntegralGraph.html
Copyright (c) 2025 Boletim da Sociedade Paranaense de Matemática

This work is licensed under a Creative Commons Attribution 4.0 International License.
When the manuscript is accepted for publication, the authors agree automatically to transfer the copyright to the (SPM).
The journal utilize the Creative Common Attribution (CC-BY 4.0).



