You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(3S,5R)-5-[(4R,5R)-4,5-dimethyl-3-oxo-2,5,6,7-tetrahydro-1H-inden-4-yl]-3-ethenyl-3-methyloxolan-2-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H24O3
assistant