You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (3R)-3-(4-chlorophenyl)-3-cyanopropanoic acid;(Z)-3-(4-chlorophenyl)-3-cyanoprop-2-enoic acid by IUPAC nomenclature, provide its molecular formula.
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C20H14Cl2N2O4
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