You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (2-chloro-6-fluorophenyl)methyl-[2-[4-(2-fluorophenyl)piperazin-1-yl]-2-oxoethyl]-methylazanium by IUPAC nomenclature, provide its molecular formula.
user
C20H23ClF2N3O+
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