You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule (E,5R)-1-[(4E,7aR)-4-[(2Z)-2-(3-hydroxy-2-methylidenecyclohexylidene)ethylidene]-7a-methyl-2,3,3a,5,6,7-hexahydro-1H-inden-1-yl]-5-ethyl-6-hydroxyhept-2-en-4-one into molecular formula.
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C28H42O3
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