You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[(3,4-difluorophenyl)methyl]-1,3,3a,4,5,6,7,7a-octahydroisoindol-4-amine;hydrochloride by IUPAC nomenclature, provide its molecular formula.
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C15H21ClF2N2
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