You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 5-(furan-2-carbonyl)-6-hydroxy-1-[(4-methoxyphenyl)methyl]-4-methyl-2-oxopyridine-3-carbonitrile by IUPAC nomenclature, provide its molecular formula.
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C20H16N2O5
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