On the generalization of harmonic graphs

Tamas Reu; Agota Dregelyi-Kiss

Author(s)

Tamas Reu Obuda University, Nepszinhaz Str. 8, Budapest H-1081, Hungary

Agota Dregelyi-Kiss Obuda University, Nepszinhaz Str. 8, Budapest H-1081, Hungary

Abstract

A possible generalization of irregular harmonic graphs is presented. Starting with the study of known properties of traditional harmonic graphs, we introduce the notion of almost harmonic graphs including irregular harmonic graphs as a subset. It is demonstrated on examples that the spectral radius (G) of an almost harmonic graph G can be estimated by simple formulas involving Zagreb indices. It is verified that if G is an almost regular graph with m edges, then (G) (M 2=m)1=2, where M 2 is the second Zagreb index of G.

Publication Details

Page(s) 16-20

DOI DOI not available

Published Journal: Discrete Mathematics Letters, Volume: 1, Issue: 0, Year: 2019

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Keywords

spectral radius, almost harmonic graph, harmonic graph, irregular harmonic graph, Zagreb indices

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