Improved Estimates of Sombor Index

Document Type : Research Paper


Faculty of Science, University of Kragujevac, Kragujevac, Serbia


‎The Sombor index $(SO)$ is a recently invented vertex-degree-based molecular structure-descriptor‎. ‎Let $M_1$ be the first Zagreb index‎. ‎The fact that $SO$ is bounded from below by $M_{1}/\sqrt{2}$ and from above by $M_{1}$ is well-known and easy to prove‎. ‎In this paper‎, ‎we improve these bounds‎.


Main Subjects

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Volume 15, Issue 1
Special Issue Dedicated to the memory of Professor Ali Reza Ashrafi (University of Kashan, I.R. Iran), who was the creator and the Editor-in-Chief of IJMC for 14 years.
March 2024
Pages 1-5