You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named (3aS,7R,7aR)-7-acetyl-3a-methyl-3-methylidene-1,2,5,6,7,7a-hexahydroinden-4-one is given. What is its corresponding molecular formula?
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C13H18O2
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