You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[[4-(dimethylamino)-3-fluorophenyl]methyl]-2-methyl-3-(2-methyl-2-piperidin-1-ylpropyl)guanidine is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H34FN5
assistant