You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-piperidin-4-yl-N-[1-(3-pyrrolidin-1-ylphenyl)ethyl]butanamide;dihydrochloride The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H35Cl2N3O
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