You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-(5,6,7,8-tetrahydroimidazo[1,2-a]pyridin-2-ylmethyl)-2-[(2R)-1,2,3,4-tetrahydronaphthalen-2-yl]acetamide into its molecular formula.
user
C20H25N3O
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