You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-(cyclopropanecarbonyl)-N-(5-ethoxy-2-methyl-2,3-dihydro-1-benzofuran-6-yl)piperidine-3-carboxamide into its molecular formula.
user
C21H28N2O4
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