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For the molecule named [3-ethyl-5-[(1E,3E,5E,7E)-7-[1-ethyl-2,4,6-trioxo-3-(sulfomethyl)-1,3-diazinan-5-ylidene]hepta-1,3,5-trienyl]-2,4,6-trioxo-1,3-diazinan-1-yl]methanesulfonic acid by IUPAC nomenclature, provide its molecular formula.
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C21H24N4O12S2
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