You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[2-[4-(5-propan-2-yl-[1,2,4]triazolo[1,5-a]pyrimidin-7-yl)piperazin-1-yl]ethyl]pyridazin-3-one by IUPAC nomenclature, provide its molecular formula.
user
C18H24N8O
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