Note on the harmonic index of a graph
نویسنده
چکیده
The harmonic index of a graph G is defined as the sum of weights 2 deg(v)+deg(u) of all edges uv of E(G), where deg(v) denotes the degree of a vertex v in V (G). In this note we generalize results of [L. Zhong, The harmonic index on graphs, Appl. Math. Lett. 25 (2012), 561– 566] and establish some upper and lower bounds on the harmonic index of G.
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ورودعنوان ژورنال:
- Ars Comb.
دوره 128 شماره
صفحات -
تاریخ انتشار 2016