You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2,4,6-trimethyl-N-[1,1,1-trifluoro-3-(1H-indol-3-yl)propan-2-yl]benzenesulfonamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H21F3N2O2S
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