You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-[4-(1,3-dimethylpyrazol-4-yl)-2,3-difluorophenyl]-1,2,3,3a,4,5,6,6a-octahydrocyclopenta[c]pyrrol-5-amine;trihydrochloride by IUPAC nomenclature, provide its molecular formula.
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C18H25Cl3F2N4
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