You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 1,4,5,9,12-pentamethyl-11,14,15,16-tetraoxatetracyclo[10.3.1.04,13.08,13]hexadecan-10-one by IUPAC nomenclature, provide its molecular formula.
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C17H26O5
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