You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-[(6-dimethylphosphorylpyridin-3-yl)methyl]-2-(5-methyl-2-thiophen-3-yl-1,3-oxazol-4-yl)acetamide by IUPAC nomenclature, provide its molecular formula.
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C18H20N3O3PS
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