You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 6-[[4-(difluoromethoxy)phenyl]methyl]-2-pyridin-3-yl-3,5,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-one into its molecular formula.
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C20H18F2N4O2
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