Abstract
An explicit combinatorial formula for the number of Kekulé structures of a hexagon-shaped benzencid system is deduced. Thus, the validity of the previously proposed, but hitherto unproved formulas of Everett (from 195'1), Woodger (from 1951), and Cyvin from 1986) is confirmed. The proof is based on the application of the John-Sachs theorem.
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Bodroža, O., Gutman, I., Cyvin, S.J. et al. Number of Kekulé structures of hexagon-shaped benzenoids. J Math Chem 2, 287–298 (1988). https://doi.org/10.1007/BF01167208
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DOI: https://doi.org/10.1007/BF01167208