TY - JOUR AU - Dehgardi, N. AU - Aram, H. PY - 2021/08/19 Y2 - 2024/03/28 TI - Bounds on the first leap Zagreb index of trees: Array JF - Carpathian Mathematical Publications JA - Carpathian Math. Publ. VL - 13 IS - 2 SE - Scientific articles DO - 10.15330/cmp.13.2.377-385 UR - https://journals.pnu.edu.ua/index.php/cmp/article/view/4403 SP - 377-385 AB - <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> ER -