Abstract
For a graph G, its sum-connectivity index is denoted by chi G and is defined as the sum of the numbers (d(u)+d(v))(-1/2) over all edges uv of G, where d(w) denotes the degree of a vertex w & ISIN;VG. In this study, we find a sharp lower bound on the sum-connectivity index of graphs having minimum degree of at least 3 under certain constraints and characterize the corresponding extremal graphs.