eng application/pdf 217314 bytes IRREGULARITY SOMBOR INDEX info:eu-repo/semantics/review All rights reserved https://phaidrabg.bg.ac.rs/o:32077 ISSN: 0561-7332 Keywords: degree (of vertex), irregularity (of graph), irregularity measure, irregularity index, Sombor index Bulletin de l'Académie Serbe des Sciences et des Arts (Classe des Sciences Mathématiques et Naturelles) 48 Gutman, Ivan Kulli, Veerabhadrappa R. Redžepović, Izudin Abstract: The irregularity Sombor index ISO is a recently introduced measure for graph irregularity, defined as the sum over all pairs of adjacent vertices u, v of the term √(|d_u^2-d_v^2 | ), where du is the degree of the vertex u. Some basic mathematical properties of ISO are established. 2023