You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[2-[(3R)-2,3-dihydro-1,4-benzodioxin-3-yl]ethyl]-6-(2-hydroxyethylamino)pyridine-3-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H21N3O4
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