You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 2-N,9-N-bis(9,9-dimethylfluoren-2-yl)-5,6-dimethylidene-2-N,9-N-diphenyldeca-1,3,7,9-tetraene-2,9-diamine by IUPAC nomenclature, provide its molecular formula.
user
C54H48N2
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