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What is the molecular formula of the compound with this IUPAC name N-[4-(4-tert-butylphenyl)phenyl]-N-[4-[9-(4-methyl-9-phenyl-4,4a-dihydrocarbazol-2-yl)carbazol-2-yl]phenyl]-9,9'-spirobi[fluorene]-4-amine ?
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C78H59N3
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