You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named tert-butyl 2-[2-(4,6-dimethyl-5-oxo-2,3-dihydropyrazin-1-ium-1-yl)ethoxy]acetate by IUPAC nomenclature, provide its molecular formula.
user
C14H25N2O4+
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