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 8-(hydroxymethyl)-3-methyl-5-propan-2-yl-2,3,3a,6,7,8a-hexahydro-1H-azulene-1,6,8-triol into molecular formula.
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C15H26O4
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