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-(4-chlorophenyl)-5-[1-(3-ethylphenyl)-5-methyltriazol-4-yl]-1,2,4-oxadiazole by IUPAC nomenclature, provide its molecular formula.
user
C19H16ClN5O
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