You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 1-(4-nitrophenyl)-2H-[1,2,4]triazolo[3,4-b][1,3]benzothiazol-9-ium by IUPAC nomenclature, provide its molecular formula.
user
C14H9N4O2S+
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