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)-4-[2-[2-(1,2-dimethylindol-3-yl)-2-(1H-indol-3-yl)ethyl]-3-methylanilino]-4-oxobut-2-enoic acid by IUPAC nomenclature, provide its molecular formula.
user
C31H29N3O3
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