Leap eccentric connectivity index in graphs with universal vertices

作者：

Highlights：

• A large number of topological indices (alias graph invariants) have been defined in mathematical chemistry with the aim of modelling chemical phenomena.

• Our goal is to investigate the extremal values of the Leap eccentric connectivity index (LECI) of graphs containing cut vertices.

• We prove an upper bound on LECI for trees of a given order and diameter, and determine the extremal trees.

• We determine trees with maximum LECI among all trees of a given order.

摘要

•A large number of topological indices (alias graph invariants) have been defined in mathematical chemistry with the aim of modelling chemical phenomena.•Our goal is to investigate the extremal values of the Leap eccentric connectivity index (LECI) of graphs containing cut vertices.•We prove an upper bound on LECI for trees of a given order and diameter, and determine the extremal trees.•We determine trees with maximum LECI among all trees of a given order.

论文关键词：Eccentricity,Leap eccentric connectivity index,Diameter,Universal vertex,Tree

论文评审过程：Received 6 May 2022, Revised 26 August 2022, Accepted 30 August 2022, Available online 12 September 2022, Version of Record 12 September 2022.

论文官网地址：https://doi.org/10.1016/j.amc.2022.127519