On Connective Eccentricity Index of Graphs
نویسندگان
چکیده
The connective eccentricity index of a graph G is defined as ξce(G) = ∑ v∈V (G) d(v) ε(v) , where ε(v) and d(v) denote the eccentricity and the degree of the vertex v, respectively. In this paper we derive upper or lower bounds for the connective eccentricity index in terms of some graph invariants such as the radius, independence number, vertex connectivity, minimum degree, maximum degree etc. Moreover, we investigate the maximal and the minimal values of connective eccentricity index among all n-vertex graphs with fixed number of pendent vertices and characterize the extremal graphs. In addition, we study the cactus on n vertices with k cycles having the maximal connective eccentricity index.
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