给定参数分子图的SDD指标的上界  

UPPER BOUND OF SYMMETRIC DIVISION DEG INDEX OF MOLECULAR GRAPHS WITH GIVEN PARAMETERS

作　　者：何雨微 刘蒙蒙 HE Yuwei;LIU Mengmeng(School of Mathematics and Science,Lanzhou Jiaotong University,Lanzhou,Gansu 730070,China)

机构地区：[1]兰州交通大学数理学院,甘肃兰州730070

出　　处：《井冈山大学学报(自然科学版)》2025年第1期8-13,共6页Journal of Jinggangshan University (Natural Science)

基　　金：国家自然科学基金项目(11961040)。

摘　　要：研究了给定边数和悬挂点数的n阶分子图和给定直径n阶分子树的SDD指标的上界,并刻画了相应的极值图。首先根据分子图的顶点、边以及顶点的度之间的关系,构建线性方程组,然后通过解线性方程组得到图G的SDD指标的一个表达式,最终确定了给定边数和悬挂点数的n阶分子图和给定直径的n阶分子树的SDD指标的上界及其达到上界的极值图。In this paper,the upper bounds of SDD index among n order molecular graphs with given edge number and pendent vertices and n order molecular trees with fixed diameter are studied,and the corresponding extremal graphs are also characterized.Firstly,based on the relationship between the vertices,edges and degrees of the graph,the system of linear equations is constructed.Then,by solving the system of linear equations,an expression of the index of the graph is obtained.Finally,the upper bounds of SDD index among all molecular graphs with given edge number and pendent vertices and molecular trees with given diameter are determined,and the corresponding extremal graphs are characterized.

关 键 词：分子图 SDD指标 极值图 

分 类 号：O157.5[理学—数学]