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 (2E)-2-ethenyl-4-methyl-4,8,11,20-tetrazatricyclo[13.3.1.13,7]icosa-1(19),2,5,7,15,17-hexaene-17-carbonitrile is given. What is its corresponding molecular formula?
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C20H23N5
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