@article{Dehgardi_Aram_2021, title={Bounds on the first leap Zagreb index of trees: Array}, volume={13}, url={https://journals.pnu.edu.ua/index.php/cmp/article/view/4403}, DOI={10.15330/cmp.13.2.377-385}, abstractNote={<p>The first leap Zagreb index $LM1(G)$ of a graph $G$ is the sum of the squares of its second vertex degrees, that is, $LM_1(G)=\sum_{v\in V(G)}d_2(v/G)^2$, where $d_2(v/G)$ is the number of second neighbors of $v$ in $G$. In this paper, we obtain bounds for the first leap Zagreb index of trees and determine the extremal trees achieving these bounds.</p>}, number={2}, journal={Carpathian Mathematical Publications}, author={Dehgardi, N. and Aram, H.}, year={2021}, month={Aug.}, pages={377–385} }