You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (E)-3-[1-[(2-chlorophenyl)methyl]indol-3-yl]-2-cyano-N-(4-ethylphenyl)prop-2-enamide by IUPAC nomenclature, provide its molecular formula.
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C27H22ClN3O
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