You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 8-[(4aR,8aR)-3,4,4a,5,6,7,8,8a-octahydro-2H-quinolin-1-yl]-1,2,3,4-tetrahydroquinoline into its molecular formula.
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C18H26N2
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