You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 5-(4-methoxyphenyl)-7-(4-methylphenyl)-4,7-dihydro-[1,2,4]triazolo[1,5-a]pyrimidine by IUPAC nomenclature, provide its molecular formula.
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C19H18N4O
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