You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[(4-methoxyphenyl)methyl]-3-(2-pyrrolidin-1-ylpyridin-4-yl)-1,2,4-oxadiazole-5-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
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C20H21N5O3
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