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What is the molecular formula of the molecule 1-[(5aS,9aS)-1-(3,4-dimethoxyphenyl)-5a,6,7,8,9,9a-hexahydro-4H-[1,2,4]triazolo[4,3-a]quinoxalin-5-yl]-2-methoxyethanone ?
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C20H26N4O4
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