Randi} Index of Benzenoid Systems and Phenylenes*
نویسندگان
چکیده
A new parameter, related to and easily determined from the structure of a benzenoid system and that of a phenylene – the number of inlets (r) – is introduced. The connectivity (Randi}) index of both benzenoid systems and phenylenes is then shown to depend solely on the number of vertices and on r. A simple relation is established between the connectivity index of a phenylene and of the corresponding hexagonal squeeze. Analogous relations are reported for the edge-connectivity indices.
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