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            | Abstract |  
            | We construct ribbon surfaces of Euler characteristic one for several infinite families of
 alternating 3-braid closures. We also use a twisted Alexander polynomial obstruction
 to conclude the classification of smoothly slice knots which are closures of alternating
 3-braids with up to 20 crossings.
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            | Keywords
                3-braids, slice-ribbon conjecture, twisted Alexander
                polynomials
               |  
          
            | Mathematical Subject Classification
                Primary: 57K10, 57K14
               |  
          
            | Milestones
                Received: 9 June 2022
               
                Accepted: 13 September 2022
               
                Published: 22 June 2023
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            | © 2023 The Author(s), under
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