You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 3-(2,6-dichlorophenyl)-N-[2-(1H-indol-2-yl)ethyl]-5-methyl-1,2-oxazole-4-carboxamide by IUPAC nomenclature, provide its molecular formula.
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C21H17Cl2N3O2
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