You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 21,25,32,35-tetrazanonacyclo[18.15.0.02,17.04,16.06,14.07,12.021,34.022,27.028,33]pentatriaconta-1(20),2(17),4(16),5,7,9,11,14,18,22(27),23,25,28(33),29,31,34-hexadecaene by IUPAC nomenclature, provide its molecular formula.
user
C31H18N4
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