You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-[(13aR)-6-oxo-2,3,4,12,13,13a-hexahydro-1H-pyrido[2,1-d][1,5]benzoxazocin-8-yl]acetamide by IUPAC nomenclature, provide its molecular formula.
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C16H20N2O3
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