You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Can you give the molecular formula of the molecule 3-(7,7,11b-trimethyl-8,9-dihydro-6aH-fluoreno[4,3-b][1]benzofuran-3-yl)-2-carbazol-9-ylbenzonitrile ?
user
C41H32N2O
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