You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 2-methyl-4-(1-methyl-2,3,4,4a,5,7,8,8a-octahydro-1,6-naphthyridin-6-yl)-2-(methylamino)butanenitrile is given. What is its corresponding molecular formula?
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C15H28N4
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