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-N-(2-chloro-4,6-dimethylphenyl)-3-N-[3-(dimethylamino)propyl]pyridine-3,5-dicarboxamide by IUPAC nomenclature, provide its molecular formula.
user
C20H25ClN4O2
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