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Can you give the molecular formula of the molecule 6-methyl-1-[2-[2-[[5-(4-nitrophenyl)furan-2-yl]methylidene]hydrazinyl]-2-oxoethyl]-[1,2,4]triazolo[4,3-b]pyridazin-1-ium-8-olate ?
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C19H15N7O5
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