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Related papers: Alternating knots with unknotting number one

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A conjecture proposed by J. Tripp in 2002 states that the crossing number of any knot coincides with the canonical genus of its Whitehead double. In the meantime, it has been established that this conjecture is true for a large class of…

Geometric Topology · Mathematics 2015-10-06 Hee Jeong Jang , Sang Youl Lee

This is the third paper in a series devoted to enumerating the prime alternating knots and links. This paper establishes a method for enumerating the prime alternating links. It is shown that one may choose any prime alternating link…

Geometric Topology · Mathematics 2007-05-23 Stuart Rankin , Ortho Smith

Surgery on a knot in $S^3$ is said to be an alternating surgery if it yields the double branched cover of an alternating link. The main theoretical contribution is to show that the set of alternating surgery slopes is algorithmically…

Geometric Topology · Mathematics 2026-05-08 Kenneth L. Baker , Marc Kegel , Duncan McCoy

A knot is an an embedding of a circle into three-dimensional space. We say that a knot is unknotted if there is an ambient isotopy of the embedding to a standard circle. By representing knots via planar diagrams, we discuss the problem of…

Geometric Topology · Mathematics 2011-11-08 Allison Henrich , Louis H. Kauffman

Introducing a way to modify knots using $n$-trivial rational tangles, we show that knots with given values of Vassiliev invariants of bounded degree can have arbitrary unknotting number (extending a recent result of Ohyama, Taniyama and…

Geometric Topology · Mathematics 2007-05-23 A. Stoimenow

We establish a Kauffman-Murasugi-Thistlethwaite-type theorem for alternating knots in a solid torus. Specifically, we show that any dotted-reduced alternating diagram of a knot in a handlebody realizes the minimal crossing number, and that…

Geometric Topology · Mathematics 2026-01-30 Lizzie Buchanan , Tanushree Shah

Frequently, knots are enumerated by their crossing number. However, the number of knots with crossing number $c$ grows exponentially with $c$, and to date computer-assisted proofs can only classify diagrams up to around twenty crossings.…

Geometric Topology · Mathematics 2018-12-03 Yoav Moriah , Jessica S. Purcell

We prove that the degree of the Brandt-Lickorish-Millet polynomial of any quasi-alternating link is less than its determinant. Therefore, we obtain a new and a simple obstruction criterion for quasi-alternateness. As an application, we…

Geometric Topology · Mathematics 2016-01-20 Khaled Qazaqzeh , Nafaa Chbili

We use Heegaard Floer homology to obtain bounds on unknotting numbers. This is a generalisation of Ozsvath and Szabo's obstruction to unknotting number one. We determine the unknotting numbers of 9_10, 9_13, 9_35, 9_38, 10_53, 10_101 and…

Geometric Topology · Mathematics 2007-05-23 Brendan Owens

Generalizing unknotting number, $n$-adjacent knots have $n$ crossings such that changing any non-empty subset of them results in the unknot. In this paper, we determine the 2-adjacent knots through 12 crossings. Using Heegaard Floer…

Geometric Topology · Mathematics 2025-10-02 John Carney , Everett Meike

Let $D$ be a diagram of an alternating knot with unknotting number one. The branched double cover of $S^3$ branched over $D$ is an L-space obtained by half integral surgery on a knot $K_D$. We denote the set of all such knots $K_D$ by…

Geometric Topology · Mathematics 2021-11-01 Andrew Donald , Duncan McCoy , Faramarz Vafaee

We show that for any nontrivial knot $K$ and any natural number $n$ there is a diagram $D$ of $K$ such that the unknotting number of $D$ is greater than or equal to $n$. It is well known that twice the unknotting number of $K$ is less than…

Geometric Topology · Mathematics 2008-06-22 Kouki Taniyama

Let $D$ be a knot diagram, and let ${\mathcal D}$ denote the set of diagrams that can be obtained from $D$ by crossing exchanges. If $D$ has $n$ crossings, then ${\mathcal D}$ consists of $2^n$ diagrams. A folklore argument shows that at…

Combinatorics · Mathematics 2017-10-19 Carolina Medina , Jorge Ramírez-Alfonsín , Gelasio Salazar

We have developed a reinforcement learning agent that often finds a minimal sequence of unknotting crossing changes for a knot diagram with up to 200 crossings, hence giving an upper bound on the unknotting number. We have used this to…

In this paper, we show that a link which has a positive and almost alternating diagram is alternating, besides that a positive and non-alternating Montesinos link has an almost positive-alternating diagram.

Geometric Topology · Mathematics 2015-10-13 Kazuhiko Inoue

Given a diagram $D$ of a knot $K$, we consider the number $c(D)$ of crossings and the number $b(D)$ of overpasses of $D$. We show that, if $D$ is a diagram of a nontrivial knot $K$ whose number $c(D)$ of crossings is minimal, then…

Geometric Topology · Mathematics 2009-11-10 Jae-Wook Chung , Xiao-Song Lin

The Jones unknot conjecture states that the Jones polynomial distinguishes the unknot from nontrivial knots. We prove it for knots up to 23 crossings.

Geometric Topology · Mathematics 2018-09-10 Robert E. Tuzun , Adam S. Sikora

The untwisting number of a knot K is the minimum number of null-homologous twists required to convert K to the unknot. Such a twist can be viewed as a generalization of a crossing change, since a classical crossing change can be effected by…

Geometric Topology · Mathematics 2024-07-24 Samantha Allen , Kenan Ince , Seungwon Kim , Benjamin Matthias Ruppik , Hannah Turner

In this article, we give a list of minimal grid diagrams of the 12 crossing prime alternating knots. This is a continuation of the work in https://doi.org/10.1142/S0218216520500765

Geometric Topology · Mathematics 2020-12-29 Gyo Taek Jin , Hwa Jeong Lee

We are giving tables of quasi-alternating knots with $8\le n \le 12$ crossings. As the obstructions for a knot to be quasialternating we used homology thickness with regards to Khovanov homology, odd homology, and Heegaard-Floer homology…

Geometric Topology · Mathematics 2014-04-23 Slavik Jablan