a note on the first geometric-arithmetic index of hexagonal systems and phenylenes
نویسندگان
چکیده
the first geometric-arithmetic index was introduced in the chemical theory as the summationof 2 du dv /(du dv ) overall edges of the graph, where du stand for the degree of the vertexu. in this paper we give the expressions for computing the first geometric-arithmetic index ofhexagonal systems and phenylenes and present new method for describing hexagonal systemby corresponding a simple graph to each hexagonal system.
منابع مشابه
A Note on the First Geometric-Arithmetic Index of Hexagonal Systems and Phenylenes
The first geometric-arithmetic index was introduced in the chemical theory as the summation of 2 du dv /(du dv ) overall edges of the graph, where du stand for the degree of the vertex u. In this paper we give the expressions for computing the first geometric-arithmetic index of hexagonal systems and phenylenes and present new method for describing hexagonal system by corresponding a simple g...
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عنوان ژورنال:
iranian journal of mathematical chemistryناشر: university of kashan
ISSN 2228-6489
دوره 2
شماره 2 2011
کلمات کلیدی
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