Open AccessLower and Upper Bounds for Hyper-Zagreb Index of Graphs
Author(s) -
Gholam Hassan Shirdel,
Hassan Rezapour,
Ramin Nasiri
Publication year - 2020
Publication title -
iraqi journal of science
Language(s) - English
Resource type - Journals
eISSN - 2312-1637
pISSN - 0067-2904
DOI - 10.24996/ijs.2020.61.6.18
Subject(s) - combinatorics , vertex (graph theory) , topological index , graph , mathematics , upper and lower bounds , connectivity , simple graph , index (typography) , discrete mathematics , computer science , mathematical analysis , world wide web
The topological indices are functions on the graph that do not depend on the labeling of their vertices. They are used by chemists for studying the properties of chemical compounds. Let be a simple connected graph. The Hyper-Zagreb index of the graph , is defined as ,where and are the degrees of vertex and , respectively. In this paper, we study the Hyper-Zagreb index and give upper and lower bounds for .