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What is the molecular formula of the molecule identified by 17-(7,7-dimethyl-5-methylideneoctan-2-yl)-10,12,13-trimethyl-2,3,4,5,6,7,8,9,11,12,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthrene ?
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C31H54
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