You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (Z)-2-cyano-3-[5-(4-fluorophenyl)thiophen-2-yl]-N-(3-methoxyphenyl)prop-2-enamide by IUPAC nomenclature, provide its molecular formula.
user
C21H15FN2O2S
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