You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-[[3-chloro-5-methoxy-4-(pyridin-3-ylmethoxy)phenyl]methyl]-1-phenylmethanamine;dihydrochloride by IUPAC nomenclature, provide its molecular formula.
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C21H23Cl3N2O2
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