You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(3E)-3-(naphthalen-1-ylmethylidene)-2-oxo-N-(2-piperidin-1-ylethyl)-1H-indole-5-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C27H27N3O2
assistant