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 2-(4-nitrophenyl)sulfanyl-5-(pyridin-1-ium-1-ylmethyl)pyridine-3-carbonitrile is given. What is its corresponding molecular formula?
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C18H13N4O2S+
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