on the harmonic index and harmonic polynomial of caterpillars with diameter four
نویسندگان
چکیده
the harmonic index h(g) , of a graph g is defined as the sum of weights 2/(deg(u)+deg(v)) of all edges in e(g), where deg (u) denotes the degree of a vertex u in v(g). in this paper we define the harmonic polynomial of g. we present explicit formula for the values of harmonic polynomial for several families of specific graphs and we find the lower and upper bound for harmonic index in caterpillars withf diameter 4.
منابع مشابه
On the harmonic index and harmonic polynomial of Caterpillars with diameter four
The harmonic index H(G) , of a graph G is defined as the sum of weights 2/(deg(u)+deg(v)) of all edges in E(G), where deg (u) denotes the degree of a vertex u in V(G). In this paper we define the harmonic polynomial of G. We present explicit formula for the values of harmonic polynomial for several families of specific graphs and we find the lower and upper bound for harmonic index in Caterpill...
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عنوان ژورنال:
iranian journal of mathematical chemistryناشر: university of kashan
ISSN 2228-6489
دوره 6
شماره 1 2015
کلمات کلیدی
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