You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named (E)-3-(3-chloro-5-ethoxy-4-methoxyphenyl)-N-[(2-fluorophenyl)methyl]-N-methylprop-2-enamide is given. What is its corresponding molecular formula?
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C20H21ClFNO3
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