You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-N,1-N,4-N,4-N-tetrakis[2-[9-(4-octylphenyl)fluoren-9-yl]phenyl]benzene-1,4-diamine into its molecular formula.
user
C138H136N2
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