You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named [(2S,10S)-2-ethyl-5-azatricyclo[10.4.0.04,9]hexadeca-1(16),4(9),5,7,12,14-hexaen-10-yl]methanamine by IUPAC nomenclature, provide its molecular formula.
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C18H22N2
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