You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 17-propyl-2,5,8,11,14-pentaoxatricyclo[10.8.0.013,18]icosa-1(12),13(18),16,19-tetraen-15-one by IUPAC nomenclature, provide its molecular formula.
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C18H22O6
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