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-fluoro-2,3-dihydro-1H-indol-5-yl)-[3-(2-methylpropyl)pyrrolidin-3-yl]methanone by IUPAC nomenclature, provide its molecular formula.
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C17H23FN2O
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