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What is the molecular formula of the compound with this IUPAC name 3-[(1R,3aS,3bS,5aR,9aR,9bS,11aR)-9a,11a-dimethyl-7-oxo-1,2,3,3a,3b,4,5,5a,6,8,9,9b,10,11-tetradecahydroindeno[5,4-f]quinolin-1-yl]propanoic acid ?
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C21H33NO3
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