The connectivity and the Harary index of a graph
نویسندگان
چکیده
The Harary index of a graph is defined as the sum of reciprocals of distances between all pairs of vertices of the graph. In this paperweprovide anupper boundof theHarary index in terms of the vertex or edge connectivity of a graph. We characterize the unique graph with themaximumHarary index among all graphs with a given number of cut vertices or vertex connectivity or edge connectivity. In addition we also characterize the extremal graphs with the second maximumHarary index among all graphs with given vertex connectivity. © 2014 Elsevier B.V. All rights reserved.
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 181 شماره
صفحات -
تاریخ انتشار 2015