You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (13R,19S,20S)-N,N,11,13,15,17,20-heptamethyl-3,21-dimethylidene-8-[4-(prop-1-en-2-ylamino)phenyl]hexacyclo[14.3.2.15,19.02,11.04,9.013,20]docosa-1,4,6,8,17-pentaen-14-amine into its molecular formula.
user
C40H48N2
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