You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-[ethyl-(3-oxo-2H-[1,2,4]triazolo[4,3-b]pyridazin-6-yl)amino]-2-methylpropanenitrile is the IUPAC name of a molecule. Please give its molecular formula.
user
C11H14N6O
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