You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 3-ethoxy-13,14-dimethylidene-15-oxatetracyclo[10.2.1.02,11.04,9]pentadeca-1,3,5,7,9,11-hexaene by IUPAC nomenclature, provide its molecular formula.
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C18H14O2
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