You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 1-[3-(methylamino)-7,8-dihydro-5H-pyrido[4,3-c]pyridazin-6-yl]-3-[(2S)-oxolan-2-yl]propan-1-one by IUPAC nomenclature, provide its molecular formula.
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C15H22N4O2
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