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Untwisting 3-strand torus knots

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 نشر من قبل Lukas Lewark
 تاريخ النشر 2019
  مجال البحث
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We prove that the signature bound for the topological 4-genus of 3-strand torus knots is sharp, using McCoys twisting method. We also show that the bound is off by at most 1 for 4-strand and 6-strand torus knots, and improve the upper bound on the asymptotic ratio between the topological 4-genus and the Seifert genus of torus knots from 2/3 to 14/27.



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