The eccentric connectivity index based on degree and eccentricity of the vertices of a graph is a widely used graph invariant in mathematics. In this paper we present the explicit generalized expressions for the eccen...The eccentric connectivity index based on degree and eccentricity of the vertices of a graph is a widely used graph invariant in mathematics. In this paper we present the explicit generalized expressions for the eccentric connectivity index and polynomial of the thorn graphs, and then consider some particular cases.展开更多
The Zagrebeccentricity indices are the eccentricity version of the classical Zagrebindices. The first Zagrebeccentricity index (E1(G)) is defined as sum of squares of the eccentricities of the vertices and the second ...The Zagrebeccentricity indices are the eccentricity version of the classical Zagrebindices. The first Zagrebeccentricity index (E1(G)) is defined as sum of squares of the eccentricities of the vertices and the second Zagrebeccentricity index (E2(G)) is equal to sum of product of the eccentricities of the adjacent vertices. In this paper we give some new upper and lower bounds for first and second Zagreb eccentricity indices.展开更多
文摘The eccentric connectivity index based on degree and eccentricity of the vertices of a graph is a widely used graph invariant in mathematics. In this paper we present the explicit generalized expressions for the eccentric connectivity index and polynomial of the thorn graphs, and then consider some particular cases.
文摘The Zagrebeccentricity indices are the eccentricity version of the classical Zagrebindices. The first Zagrebeccentricity index (E1(G)) is defined as sum of squares of the eccentricities of the vertices and the second Zagrebeccentricity index (E2(G)) is equal to sum of product of the eccentricities of the adjacent vertices. In this paper we give some new upper and lower bounds for first and second Zagreb eccentricity indices.
