You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
methane;(1R,9R,14R)-9,13,13-trimethyl-5-propyl-8-oxatetracyclo[7.4.1.02,7.012,14]tetradeca-2,4,6-trien-3-ol is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H30O2
assistant