You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 1-[2-(2,4-difluorophenoxy)acetyl]-2,3,3a,4,5,6,7,7a-octahydroindole-2-carboxylic acid into molecular formula.
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C17H19F2NO4
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