on the harmonic index of graph operations

Authors

b. shwetha shetty

v. lokesha

p. s. ranjini

abstract

‎the harmonic index of a connected graph $g$‎, ‎denoted by $h(g)$‎, ‎is‎ ‎defined as $h(g)=sum_{uvin e(g)}frac{2}{d_u+d_v}$‎ ‎where $d_v$ is the degree of a vertex $v$ in g‎. ‎in this paper‎, ‎expressions for the harary indices of the‎ ‎join‎, ‎corona product‎, ‎cartesian product‎, ‎composition and symmetric difference of graphs are‎ ‎derived‎.

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Journal title:
transactions on combinatorics

Publisher: university of isfahan

ISSN 2251-8657

volume 4

issue 4 2015

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