You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[3,4-dimethyl-2-[2-(2-methylprop-2-enoyloxy)ethyl]phenyl]ethyl 2-methylprop-2-enoate by IUPAC nomenclature, provide its molecular formula.
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C20H26O4
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