First and second extremal bipartite graphs with respect to PI index
نویسندگان
چکیده
منابع مشابه
First and second extremal bipartite graphs with respect to PI index
The Padmakar–Ivan (PI) index of a graph G is defined as the sum of terms [mu(e) + mv(e)] over all edges of G, where e is an edge, connecting the vertices u and v, wheremu(e) is the number of edges of G lying closer to the vertex u than to the vertex v, and where mv(e) is defined analogously. The extremal values of the PI index are determined in the class of connected bipartite graphs with a giv...
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ژورنال
عنوان ژورنال: Mathematical and Computer Modelling
سال: 2011
ISSN: 0895-7177
DOI: 10.1016/j.mcm.2011.06.001