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-[2-[4-(4-chloro-3-methoxyphenyl)piperazin-1-yl]-2-oxoethyl]-N-(4-ethoxyphenyl)formamide by IUPAC nomenclature, provide its molecular formula.
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C22H26ClN3O4
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