You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-N,4-N-dimethyl-2-(1,2,3,4-tetrahydronaphthalen-2-yl)benzene-1,4-dicarboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H22N2O2
assistant