You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (1S,13R)-12-oxapentacyclo[11.8.0.02,11.04,9.014,19]henicosa-2(11),4,6,8,14,16,18-heptaene-3,10-dione into its molecular formula.
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C20H14O3
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