You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(4-fluoro-2-methylphenyl)-[(3S)-3-(3-phenyl-1,2,4-oxadiazol-5-yl)piperidin-1-yl]methanone The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H20FN3O2
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