You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 13-chloro-6-nitro-2-piperidin-4-yl-4-azatricyclo[9.4.0.03,8]pentadeca-1(11),3(8),4,6,12,14-hexaene by IUPAC nomenclature, provide its molecular formula.
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C19H20ClN3O2
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