You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Under IUPAC nomenclature, a molecule named 4-oxo-N-(4-propan-2-ylphenyl)-6,7-dihydro-5H-1-benzofuran-2-carboxamide is given. What is its corresponding molecular formula?
user
C18H19NO3
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