Enumeration of cyclic polyazulenoids
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A cyclic polyazulenoid structure is a kind of nonalternant conjugated hydrocarbon consisting of a cyclic series of alternatingly fused five membered rings and seven membered rings, which forms a “belt of rings” or say, “belt of azulenes”, more precisely. We give the exact counting formula for the number of cyclic polyazulenoid isomers according to the number of azulene units, by a method based on a generalization of Pólya’s Theorem.
KeywordsCyclic polyazulenoids Enumeration Pólya’s Theorem
Mathematics Subject Classification92E10 05C30 05C90
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