Harary index of product graphs

نویسندگان

  • K. Pattabiraman
  • P. Paulraja
چکیده

The Harary index is defined as the sum of reciprocals of distances between all pairs of vertices of a connected graph. In this paper, the exact formulae for the Harary indices of tensor product G × Km0,m1,...,mr−1 and the strong product G⊠Km0,m1,...,mr−1 , whereKm0,m1,...,mr−1 is the complete multipartite graph with partite sets of sizes m0,m1, . . . ,mr−1 are obtained. Also upper bounds for the Harary indices of tensor and strong products of graphs are estabilished. Finally, the exact formula for the Harary index of the wreath product G ◦G is obtained.

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عنوان ژورنال:
  • Discussiones Mathematicae Graph Theory

دوره 35  شماره 

صفحات  -

تاریخ انتشار 2015