You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 7,7-dimethyl-1,2,4,5,6,8-hexahydroheptalen-3-one;(3Z,5E,7Z)-5,6-dimethylnona-3,5,7-trien-2-one;ethane;propane by IUPAC nomenclature, provide its molecular formula.
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