Bounds on Augmented Zagreb Index of Graphs

Abstract:

      Let $G=(V,E)$ be a simple connected graph with $n~(n\geq 3)$ vertices and $m$ edges, with vertex degree sequence $\{d_{1}, d_{2},\ldots, d_{n}\}$. The augmented Zagreb index is defined as $AZI=AZI(G)=\sum_{ij\in E}(\frac{d_{i}d_{j}}{d_{i}+d_{j}-2})^{3}$. Using the properties of inequality, we investigate the bounds of $AZI$ for connected graphs, in particular unicyclic graphs in this paper, some useful conclusions are obtained.