The concept of arithmetic-geometric index was recently introduced in chemical graph theory, but it has proven to be useful from both a theoretical and practical point view. aim this paper is obtain new bounds the characterize extremal graphs with respect them. Several are based on other indices, such as second variable Zagreb or general atom-bond connectivity index), some them involve parameter...

For a nontrivial graph G, its first and second Zagreb coindices are defined [1], respectively, as M1(G) = ∑ uv ∈E(G) (dG(u)+dG(v)) and M2(G) = ∑ uv ∈E(G) dG(u)dG(v), where dG(x) is the degree of vertex x in G. In this paper, we obtained some new properties of Zagreb coindices. We mainly give explicit formulae for the first Zagreb coindex of line graphs and total graphs. Mathematics Subject Clas...

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...

Given a tree T = (V,E), the second Zagreb index of T is denoted by M2(T ) = ∑ uv∈E d(u)d(v) and the Wiener polarity index of T is equal to WP (T ) = ∑ uv∈E(d(u)−1)(d(v)−1). Let π = (d1, d2, ..., dn) and π′ = (d1, d2, ..., dn) be two different non-increasing tree degree sequences. We write π π′, if and only if ∑n i=1 di = ∑n i=1 d ′ i, and ∑j i=1 di ≤ ∑j i=1 d ′ i for all j = 1, 2, ..., n. Let Γ...

The F-index of a graph is defined as the sum of cubes of the vertex degrees of the graph which was introduced in 1972, in the same paper where the first and second Zagreb indices were introduced. In this paper we study the F-index of four operations on graphs which were introduced by Eliasi and Taeri [M. Eliasi, B. Taeri, Four new sums of graphs and their Wiener indices, Discrete Appl. Math.157...

The area of graph theory (GT) is rapidly expanding and playing a significant role in cheminformatics, mostly mathematics chemistry to develop different physicochemical, chemical structure, their properties. manipulation study graphical details are made feasible by using numerical structure invariant. Investigating these characteristics topological indices (TIs) possible the discipline mathemati...