You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named (2S)-2-(4-aza-1-azoniabicyclo[2.2.2]octan-1-yl)-1-[(2R)-2-methyl-2,3-dihydroindol-1-yl]propan-1-one is given. What is its corresponding molecular formula?
user
C18H26N3O+
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