You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule 2-(azepan-1-ylmethylideneamino)-5,5,7,7-tetramethyl-4,6-dihydrothieno[2,3-c]pyridin-6-ium-3-carbonitrile .
user
C19H29N4S+
assistant