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What is the molecular formula of the molecule (4R)-4-[(5R,10S,13S,14S,17S)-4,4,10,13,14-pentamethyl-3-oxo-1,2,5,6,7,11,12,15,16,17-decahydrocyclopenta[a]phenanthren-17-yl]pentanal ?
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C27H42O2
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