You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance (1R,4aS,8aS)-7-methyl-4-methylidene-1-propan-2-yl-2,3,4a,5,8,8a-hexahydro-1H-naphthalene .
user
C15H24
assistant