You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 7-[(2,3-dimethoxyphenyl)methyl]-6,8-dihydro-5H-pyrido[3,4-d]pyrimidin-4-amine by IUPAC nomenclature, provide its molecular formula.
user
C16H20N4O2
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