You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 4-(3,4-dihydro-2H-quinolin-1-yl)-N-(5-fluoro-2-methylphenyl)-4-oxobut-2-enamide by IUPAC nomenclature, provide its molecular formula.
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C20H19FN2O2
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