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-(2,4-difluorophenyl)-2-[[(R)-(4-methylphenyl)-thiophen-2-ylmethyl]amino]acetamide is given. What is its corresponding molecular formula?
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C20H18F2N2OS
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