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 1-(3-bicyclo[4.1.0]hepta-2,4-dienyl)-3-methyl-2-(2-methylphenyl)imidazol-3-ium is given. What is its corresponding molecular formula?
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C18H19N2+
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