Extremal symmetric division deg index of molecular trees and molecular graphs with fixed number of pendant vertices

作者:

Highlights:

• We identify the extremal trees with respect to symmetric division deg index among all molecular trees with fixed number of pendant vertices.

• We get a lower bound on symmetric division deg index for all molecular (n,m,p)-graphs (n-order molecular graphs with m≥n edges and p>0 pendant vertices).

• The method is to classify the set of edges of the molecular graph according to the degree of the two endpoints of each edge, and then use the two key formulas established in Lemma 2.2.

摘要

•We identify the extremal trees with respect to symmetric division deg index among all molecular trees with fixed number of pendant vertices.•We get a lower bound on symmetric division deg index for all molecular (n,m,p)-graphs (n-order molecular graphs with m≥n edges and p>0 pendant vertices).•The method is to classify the set of edges of the molecular graph according to the degree of the two endpoints of each edge, and then use the two key formulas established in Lemma 2.2.

论文关键词:Symmetric division deg index,Molecular tree,Molecular graph,Pendant vertex

论文评审过程:Received 4 May 2022, Revised 15 July 2022, Accepted 20 July 2022, Available online 8 August 2022, Version of Record 8 August 2022.

论文官网地址:https://doi.org/10.1016/j.amc.2022.127438