You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 7,7-dimethyl-2-pyridin-2-yl-1,5,6,8-tetrahydroimidazo[4,5-c]azepin-4-one by IUPAC nomenclature, provide its molecular formula.
user
C14H16N4O
assistant