You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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What is the molecular formula of the molecule 2-(3,4a,5,6,7,7a-hexahydro-2H-cyclopenta[b][1,4]oxazin-4-yl)-1-(4-chlorophenyl)propan-1-one ?
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C16H20ClNO2
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