You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (2R,3aS,7aS)-N-(2-methoxyethyl)-6-(2-phenylethyl)-3,3a,4,5,7,7a-hexahydro-2H-furo[2,3-c]pyridine-2-carboxamide;2,2,2-trifluoroacetic acid by IUPAC nomenclature, provide its molecular formula.
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C21H29F3N2O5
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