You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(3S)-3-(3-benzyl-2H-tetrazol-4-yl)-8-fluoro-1,3,4,5-tetrahydro-1-benzazepin-2-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H18FN5O
assistant