You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-methoxy-4-[[(1S,12R)-7-methyl-4,8,9,15-tetrazatetracyclo[10.2.1.02,10.05,9]pentadeca-2(10),3,5,7-tetraen-15-yl]methyl]phenol by IUPAC nomenclature, provide its molecular formula.
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C20H22N4O2
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