You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[3-[3-(9-phenylcarbazol-3-yl)carbazol-9-yl]phenyl]-3-azatetracyclo[7.6.1.05,16.010,15]hexadeca-1(16),2,4,6,8,10,12,14-octaene by IUPAC nomenclature, provide its molecular formula.
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C51H31N3
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