You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[3-[5-(2-chlorophenyl)-1,2,4-oxadiazol-3-yl]phenoxy]-N-propan-2-ylacetamide by IUPAC nomenclature, provide its molecular formula.
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C19H18ClN3O3
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