You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 18-oxapentacyclo[11.5.1.02,11.04,9.017,19]nonadeca-1(19),2,4(9),5,10,12,14,16-octaene into its molecular formula.
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C18H12O
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