You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[7,7-bis(2,2-dimethylpropyl)-3-methylfluoreno[2,3-b][1]benzofuran-4-yl]-1,4-dimethyl-5-propan-2-ylpyridin-1-ium is the IUPAC name of a molecule. Please give its molecular formula.
user
C40H48NO+
assistant