You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3,3,5,7a-tetramethyl-1,1a,2,4,5,6,7,7b-octahydrocyclopropa[h]azulene-2,4a,6-triol The above is the IUPAC name of a molecule. Write its molecular formula.
user
C15H26O3
assistant