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 identified by methyl 4-[(4aR,8aR)-3,4,4a,5,6,7,8,8a-octahydro-2H-quinolin-1-yl]-2-(methylamino)butanoate ?
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C15H28N2O2
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