Some new bounds on the modified first Zagreb index

Document Type : Original paper


1 Faculty of Electronic Engineering, University of Nis, Nis, Serbia

2 Faculty of Electronic Engineering

3 University of Hail, Saudi Arabia


Let $G$ be a graph containing no isolated vertices. For the graph $G$, its modified first Zagreb index is defined as the sum of reciprocals of squares of vertex degrees of $G$. This article provides some new bounds on the modified first Zagreb index of $G$ in terms of some other well-known graph invariants of $G$. From the obtained bounds, several known results follow directly.


Main Subjects

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