You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named [(4aS,7aS)-1,2,3,4,4a,5,7,7a-octahydropyrrolo[3,4-b]pyridin-6-yl]-(4-tert-butylcyclohexyl)methanone by IUPAC nomenclature, provide its molecular formula.
user
C18H32N2O
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