You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 1-(1-cyclopropylcyclopropyl)-5-propyl-3,3a,6,7,8,9-hexahydro-[1,2,4]triazolo[4,3-a]quinoxalin-4-one into its molecular formula.
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C18H26N4O
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