You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 23,27,29,34-tetrazanonacyclo[18.15.0.02,17.04,16.07,15.09,14.021,26.027,35.028,33]pentatriaconta-1(20),2(17),4(16),5,7(15),9,11,13,18,21(26),22,24,28(33),29,31,34-hexadecaene by IUPAC nomenclature, provide its molecular formula.
user
C31H18N4
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