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-(3,4-dimethylthieno[2,3-b]thiophen-5-yl)-3-naphthalen-1-yl-2-benzothiophene is given. What is its corresponding molecular formula?
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C26H18S3
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