Extremal k∗-Cycle Resonant Hexagonal Chains
نویسندگان
چکیده
Denote by B∗ n the set of all k∗-cycle resonant hexagonal chains with n hexagons. For any Bn ∈ B ∗ n , let m(Bn) and i(Bn) be the numbers of matchings (=the Hosoya index) and the number of independent sets (=the Merrifield-Simmons index) of Bn, respectively. In this paper, we give a characterization of the k∗-cycle resonant hexagonal chains, and show that for any Bn ∈ B ∗ n , m(Hn) ≤ m(Bn) and i(Hn) ≥ i(Bn), where Hn is the helicene chain. Moreover, equalities hold only if Bn = Hn.
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