You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-phenyl-3,10-diaza-4-azoniatetracyclo[11.4.0.02,6.07,12]heptadeca-1(17),2(6),4,7(12),8,10,13,15-octaene is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H14N3+
assistant