You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named N-[[3-(4-ethoxyphenyl)-1,2,4-oxadiazol-5-yl]methyl]-N-(thiophen-2-ylmethyl)ethanamine is given. What is its corresponding molecular formula?
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C18H21N3O2S
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