New inequalities involving the Geometric-Arithmetic index

J. M. Rodriguez, J. A. Rodriguez-Velazquez, J. M. Sigarreta

Let $G=(V,E)$ be a simple connected graph and $d_i$ be the degree of its $i$th vertex. In a recent paper [J. Math. Chem. 46 (2009) 1369-1376] the first geometric-arithmetic index o…