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system
Provide the molecular formula for the IUPAC named substance N-[(3aR,6aS)-5-(dimethylamino)-1,2,3,3a,4,5,6,6a-octahydropentalen-2-yl]-N-methyl-2-[4-(trifluoromethyl)phenyl]acetamide .
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C20H27F3N2O
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