The concept of Sombor index (SO) was recently introduced by Gutman in the chemical graph theory. It is a vertex-degree-based topological and denoted SO: SO=SO(G)=?vivj?E(G)dG(vi)2+dG(vj)2, where dG(vi) degree vertex vi G. Here, we present novel lower upper bounds on graphs using some parameters. Moreover, obtain several relations with first second Zagreb indices graphs. Finally, give conclusion...

In this paper we study lower bounds in a unified way for large family of topological indices, including the first variable Zagreb index M 1 ? . Our aim is to obtain sharp inequalities and characterize corresponding extremal graphs. The main results provide several vertex-degree-based indices. These are new even Zagreb, inverse forgotten

The molecular topology of a graph is described by topological indices, which are numerical measures. In theoretical chemistry, indices quantities that used to represent the networks. These can be calculate several physical and chemical properties compounds, such as boiling point, entropy, heat generation, vaporization enthalpy. Graph theory comes in handy when looking at link between certain so...

The reformulated Zagreb indices of a graph is obtained from the classical Zagreb by replacing vertex degree by edge degree and are defined as sum of squares of the degree of the edges and sum of product of the degrees of the adjacent edges. In this paper we give some explicit results for calculating the first and second reformulated Zagreb indices of dendrimers. Mathematics Subject Classificati...

There is a natural linkage between the molecular structures and the bio-medical and pharmacology characteristics. A topological index can be considered as transformation of chemical structure in to real number and has been used as a predictor parameter. There are certain vertex-degree-based topological indices which has been used extensively in the chemical graph theory but recently no further ...

The augmented eccentric connectivity index of a graph which is a generalization of eccentric connectivity index is defined as the summation of the quotients of the product of adjacent vertex degrees and eccentricity of the concerned vertex of a graph. In this paper we established some relationships between augmented eccentric connectivity index and several other graph invariants like number of ...