Science and Technology Indonesia
Vol. 11 No. 2 (2026): April

Relation Between Randic and Harmonic Energies of Commuting Graph for Dihedral Groups

Romdhini, Mamika Ujianita (Unknown)
Nawawi, Athirah (Unknown)



Article Info

Publish Date
13 Mar 2026

Abstract

Consider a finite group G with center Z(G). This work examines the commuting graph $\Gamma_G$, a graph constructed from a group $G$ whose vertices correspond precisely to the noncentral elements of the group, that is, all elements in $G$ except those belonging to its center $Z(G)$. The graph is defined on the vertex set $G\backslash Z(G)$, where two distinct vertices vp and vq are joined by an edge precisely when they commute, that is, whenever vp vq=vq vp. The number of vertices adjacent to vp is denoted as dvp, which is the degree of vp. The Randic and harmonic matrices of $\Gamma_G$ are defined as square matrices in which $(p,q)-$th entry are $\frac{1}{\sqrt{d_{v_p} \cdot d_{v_q}} }$ and $\frac{2}{d_{v_p}+d_{v_q} }$ if $v_p$ and $v_q$ are adjacents, respectively; otherwise, it is zero. Randic energy is the sum of the absolute eigenvalues of the Randic matrix whereas harmonic energy is the sum of the absolute eigenvalues of the harmonic matrix. In this paper, we compare the Randic and harmonic energies of the commuting graph for non-abelian dihedral group of order 2n, D2n.

Copyrights © 2026






Journal Info

Abbrev

JSTI

Publisher

Subject

Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Environmental Science Materials Science & Nanotechnology Physics

Description

An international Peer-review journal in the field of science and technology published by The Indonesian Science and Technology Society. Science and Technology Indonesia is a member of Crossref with DOI prefix number: 10.26554/sti. Science and Technology Indonesia publishes quarterly (January, April, ...