University of Kashan Iranian Journal of Mathematical Chemistry 2228-6489 5 2 2014 11 01 Upper and Lower Bounds of Symmetric Division Deg Index 91 98 7357 10.22052/ijmc.2014.7357 EN Alexander Vasilyev University of Primorska, IAM Journal Article 2014 07 02 Symmetric Division Deg index is one of the 148 discrete Adriatic indices that showed good predictive properties on the testing sets provided by International Academy of Mathematical Chemistry. Symmetric Division Deg index is defined by $$ SDD(G) = sumE left( frac{min{d_u,d_v}}{max{d_u,d_v}} + frac{max{d_u,d_v}}{min{d_u,d_v}} right), $$ where $d_i$ is the degree of vertex $i$ in graph $G$. In this paper we provide lower and upper bounds of SDD index in some classes of graphs and determine the corresponding extremal graphs. https://ijmc.kashanu.ac.ir/article_7357_78bfab656717a8a35de2906a6ca46a99.pdf