journal-of-discrete-mathematical-sciences-and-cryptography Journal of Discrete Mathematical Sciences and Cryptography 2169-0065 0972-0529 Taru Publications 10.47974/JDMSC-1845 Reduced Sombor index of graphs Dorjsembe Shiikhar Department of Mathematics, Mongolian National University of Education, Baga Toiruu 14, Ulaanbaatar, Mongolia Buyantogtokh Lkhagva Department of Mathematics, Mongolian National University of Education, Baga Toiruu 14, Ulaanbaatar, Mongolia Horoldagva Batmend Department of Mathematics, Mongolian National University of Education, Baga Toiruu 14, Ulaanbaatar, Mongolia 28 1 77 86 28 02 2025

Gutman developed the concept of Sombor indices and it was shown that any vertex degree-based graph invariant can be viewed as a reduced Sombor-type index. In the paper, we investigate extremal graphs concerning the reduced Sombor index for trees, unicyclic graphs, and the class of graphs with a given number of vertices and cut edges (pendent vertices).

 Cut edge Maximum degree Reduced sombor index Pendent vertex access open retracted no