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 tert-butyl N-[4-cyclopropyl-1-[(4-methylpyridin-3-yl)amino]-1-oxobutan-2-yl]carbamate is given. What is its corresponding molecular formula?
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C18H27N3O3
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