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 (9-amino-3-bicyclo[3.3.1]nonanyl)-[4-(3-methoxyphenyl)piperazin-1-yl]methanone is given. What is its corresponding molecular formula?
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C21H31N3O2
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