Extremal Kragujevac trees with respect to Sombor indices

Document Type : Original paper


1 Department of Mathematics, National University of Mongolia, Ulaanaatar, Mongolia

2 Department of Mathematics, Mongolian National University of Education


The concept of the Sombor indices of a graph was introduced by Gutman. A vertex-edge variant of the Sombor index of graphs is called the KG-Sombor index.  Recently, the Sombor and  KG-Sombor indices of Kragujevac trees were studied, and the extremal Kragujevac trees with respect to these indices were empirically  determined.   Here we give analytical proof of the results.


Main Subjects

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