You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 3-(3-fluorophenyl)-2-(4-fluorophenyl)-8-[4-(trifluoromethyl)phenyl]-3H-imidazo[1,5-a]pyridine by IUPAC nomenclature, provide its molecular formula.
user
C26H17F5N2
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