You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-(4,6-dimethylpyrimidin-2-yl)sulfonyl-N-(1,2,3,5,6,7-hexahydro-s-indacen-4-yl)acetamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H23N3O3S
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