You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 5,14-dioxa-3,9,12-triazabicyclo[18.4.0]tetracosa-1,3,6,8,10,12,15,17,19,21,23-undecaene-8-carboxamide by IUPAC nomenclature, provide its molecular formula.
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C20H18N4O3
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