You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule 3-[2-methyl-1-(3-propan-2-yl-1-bicyclo[1.1.1]pentanyl)propan-2-yl]bicyclo[1.1.1]pentane-1-carbonitrile .
user
C18H27N
assistant