You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 3,15-bis(9-phenylcarbazol-3-yl)-15-azatetracyclo[10.2.1.05,14.08,13]pentadeca-1(14),2,4,6,8(13),9,11-heptaene into its molecular formula.
user
C50H31N3
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