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)-1-methyl-N-[(2S)-3-methyl-1-(methylamino)-1-oxobutan-2-yl]piperidine-2-carboxamide by IUPAC nomenclature, provide its molecular formula.
user
C13H25N3O2
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