You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named N-(2,6-dimethylphenyl)-2-[4-[(6-ethyl-2-oxochromen-4-yl)methyl]piperazin-1-yl]acetamide by IUPAC nomenclature, provide its molecular formula.
user
C26H31N3O3
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