Sharp bounds on the reduced second Zagreb index of graphs with given number of cut vertices

摘要

The first Zagreb index M-1 of a graph is defined as the sum of the square of every vertex degree, and the second Zagreb index M-2 of a graph is defined as the sum of the product of vertex degrees of each pair of adjacent vertices. In Furtula et al. (2014) Furtula, Gutman and Ediz first proposed the reduced second Zagreb index as