You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named (1S)-1-(2-chlorophenyl)-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indol-2-ium is given. What is its corresponding molecular formula?
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C17H16ClN2+
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