You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (2S)-1-(2,4-dichlorophenoxy)-3-[4-(4-methoxyphenyl)piperazin-1-ium-1-yl]propan-2-ol by IUPAC nomenclature, provide its molecular formula.
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C20H25Cl2N2O3+
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