You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named ethyl 2-methyl-5-oxo-7-propan-2-ylidene-4-pyridin-3-yl-8H-quinoline-3-carboxylate by IUPAC nomenclature, provide its molecular formula.
user
C21H22N2O3
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