You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 9,9-dimethyl-9-silapentacyclo[9.2.2.24,7.02,10.03,8]heptadeca-2(10),3(8)-diene by IUPAC nomenclature, provide its molecular formula.
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C18H26Si
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