You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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4-(2,3-dihydro-1H-inden-5-yl)-4-oxo-N-[(6-pyrrolidin-1-ylpyridin-3-yl)methyl]butanamide is the IUPAC name of a molecule. Please give its molecular formula.
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C23H27N3O2
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