You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-[4-(3-oxo-6,7-dihydro-5H-cyclopenta[c]pyridazin-2-yl)oxolan-3-yl]-1H-indole-5-carboxamide into its molecular formula.
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C20H20N4O3
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