You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named [4-[(4-chlorophenyl)methyl]piperazin-1-yl]-[3-[(3-methyl-4-nitrophenoxy)methyl]phenyl]methanone by IUPAC nomenclature, provide its molecular formula.
user
C26H26ClN3O4
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