You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (3S,10R,13S)-10,13-dimethyl-6,7,8,9,11,12,14,15,16,17-decahydro-3H-cyclopenta[a]phenanthren-3-ol by IUPAC nomenclature, provide its molecular formula.
user
C19H28O
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