You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 1-[4-[2-(2-chlorophenoxy)ethyl]piperazin-1-yl]-2-(2-methyl-1H-indol-3-yl)ethanone by IUPAC nomenclature, provide its molecular formula.
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C23H26ClN3O2
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