Trees of extremal connectivity index
نویسندگان
چکیده
The connectivity index wα(G) of a graph G is the sum of the weights (d(u)d(v)) of all edges uv of G, where α is a real number (α 6= 0), and d(u) denotes the degree of the vertex u. Let T be a tree with n vertices and k pendant vertices. In this paper, we give sharp lower and upper bounds for w1(T ). Also, for −1 ≤ α < 0, we give a sharp lower bound and a upper bound for wα(T ).
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عنوان ژورنال:
- Discrete Applied Mathematics
دوره 154 شماره
صفحات -
تاریخ انتشار 2006