You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 7'-(2-pyren-1-ylphenyl)spiro[fluorene-9,12'-pentacyclo[11.8.0.02,11.05,10.014,19]henicosa-1(13),2(11),3,5(10),6,8,14,16,18,20-decaene] by IUPAC nomenclature, provide its molecular formula.
user
C55H32
assistant