You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 4-[4-[(4-fluorophenyl)methyl]-1,4-diazepan-1-yl]-6-[(3R)-oxolan-3-yl]pyrimidin-2-amine into its molecular formula.
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C20H26FN5O
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