You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 9-(3,3-dimethylbutyl)-3-ethenyl-8-ethyl-6,6-dimethyl-5H-benzo[b]carbazol-11-one is given. What is its corresponding molecular formula?
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C28H33NO
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