You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2'-(1H-indol-3-yl)spiro[1-azabicyclo[2.2.2]octane-3,5'-4H-1,3-oxazole] is the IUPAC name of a molecule. Please give its molecular formula.
user
C17H19N3O
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