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What is the molecular formula of the compound with this IUPAC name (2Z,8R,9S,10S,13S,14S,17S)-17-hydroxy-2-(hydroxymethylidene)-10,13-dimethyl-4,5,6,7,8,9,11,12,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-3-one ?
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C20H30O3
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