You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 1-(3-cyclobutyl-[1,2,4]triazolo[4,3-b]pyridazin-6-yl)-N-methyl-N-(pyrimidin-5-ylmethyl)azetidin-3-amine is given. What is its corresponding molecular formula?
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C18H22N8
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