You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-[[2-(1,3,4,6,7,8,9,9a-octahydropyrido[1,2-a]pyrazin-2-yl)cyclobutyl]methyl]propan-1-amine into its molecular formula.
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C16H31N3
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