You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 4-(8-methoxy-1,3,4,5-tetrahydropyrido[4,3-b]indol-2-yl)-N-(3-methylbutyl)-4-oxobutanamide is given. What is its corresponding molecular formula?
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C21H29N3O3
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