You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 9-[(1,5-dimethylpyrazol-4-yl)methyl]-N-ethyl-9-azabicyclo[3.3.1]nonan-3-amine by IUPAC nomenclature, provide its molecular formula.
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C16H28N4
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