You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 6-[(2Z)-3-[2-[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]ethyl]-3-methyl-2-[(E)-3-[3-methyl-5-sulfo-1,3-bis(3-sulfopropyl)indol-1-ium-2-yl]prop-2-enylidene]-5-sulfoindol-1-yl]hexanoic acid by IUPAC nomenclature, provide its molecular formula.
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C42H61N2O18S4+
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