You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2Z)-5-chloro-2-[7-(5-chloro-1,3,3-trimethyl-3a,7a-dihydroindol-1-ium-2-yl)hepta-2,4,6-trienylidene]-1,3,3-trimethylindole The above is the IUPAC name of a molecule. Write its molecular formula.
user
C29H33Cl2N2+
assistant