You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (2E)-2-[2-[[(E)-(4,6-difluoro-2,3-dihydroinden-1-ylidene)amino]oxymethyl]-3-methylphenyl]-2-methoxyimino-N-methylacetamide by IUPAC nomenclature, provide its molecular formula.
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C21H21F2N3O3
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