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 3-(benzimidazol-1-yl)-N-(4,5,6,7-tetrahydro-1-benzofuran-4-yl)propanamide is given. What is its corresponding molecular formula?
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C18H19N3O2
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