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Related papers: Equivariant crossing numbers for two-bridge knots

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Previous work used polygonal realizations of knots to reduce the problem of computing the superbridge number of a realization to a linear programming problem, leading to new sharp upper bounds on the superbridge index of a number of knots.…

Geometric Topology · Mathematics 2022-11-14 Clayton Shonkwiler

Using computer calculations and working with representatives of pretzel tangles we established general adequacy criteria for different classes of knots and links. Based on adequate graphs obtained from all Kauffman states of an alternating…

Geometric Topology · Mathematics 2008-11-04 Slavik Jablan

Traditionally, knot theorists have considered projections of knots where there are two strands meeting at every crossing. A triple crossing is a crossing where three strands meet at a single point, such that each strand bisects the…

Geometric Topology · Mathematics 2018-05-14 Daishiro Nishida

We describe a method of encoding various types of link diagrams, including those with classical, flat, rigid, welded, and virtual crossings. We show that this method may be used to encode link diagrams, up to equivalence, in a notation…

Geometric Topology · Mathematics 2013-05-03 Chad Musick

A rational knot or link can be put into a standard alternating format which has horizontal and vertical twist sites (double helices). The number and type of these twist sites are determined by terms of next-to-highest $z$-degree in…

Geometric Topology · Mathematics 2014-10-02 Mark E. Kidwell , Kerry M. Luse

It is known that each knot has a semimeander diagram (i. e. a diagram composed of two smooth simple arcs), however the number of crossings in such a diagram can only be roughly estimated. In the present paper we provide a new estimate of…

Geometric Topology · Mathematics 2026-03-26 Yury Belousov

We determine a simple condition on a particular state graph of an alternating knot or link diagram that characterizes when the unoriented genus and crosscap number coincide, extending work of Adams and Kindred. Building on this same work…

Geometric Topology · Mathematics 2025-08-07 Moshe Cohen , Thomas Kindred , Adam M. Lowrance , Patrick D. Shanahan , Cornelia A. Van Cott

The 2-bridge knots are a family of knots with bridge number 2. In this paper, we compute the Kauffman polynomials of 2-bridge knots using the Kauffman skein theory and linear algebra techniques. Our calculation can be easily carried out…

Geometric Topology · Mathematics 2007-05-23 Bin Lu , Jianyuan K. Zhong

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

We study relations between unknotting number and crossing number of a spatial embedding of a handcuff-graph and a theta curve. It is well known that for any non-trivial knot $K$ twice the unknotting number of $K$ is less than or equal to…

Geometric Topology · Mathematics 2021-03-23 Yuta Akimoto

We use grid diagrams to give a combinatorial algorithm for computing the knot Floer homology of the pullback of a knot K in its m-fold cyclic branched cover Sigma^m(K), and we give computations when m=2 for over fifty three-bridge knots…

Geometric Topology · Mathematics 2016-01-20 Adam Simon Levine

The concordance genus of a knot K is the minimum three-genus among all knots concordant to K. For prime knots of 10 or fewer crossings there have been three knots for which the concordance genus was unknown. Those three cases are now…

Geometric Topology · Mathematics 2014-10-01 Charles Livingston

The bridge index and superbridge index of a knot are important invariants in knot theory. We define the bridge map of a knot conformation, which is closely related to these two invariants, and interpret it in terms of the tangent indicatrix…

Geometric Topology · Mathematics 2012-05-24 Colin Adams , Dan Collins , Katherine Hawkins , Charmaine Sia , Robert Silversmith , Bena Tshishiku

A long standing open conjecture states that if a link $\mathcal{K}$ is alternating, then its ropelength $L(\mathcal{K})$ is at least of the order $O(Cr(\mathcal{K}))$. A recent result shows that the maximum braid index of a link bounds the…

Geometric Topology · Mathematics 2021-08-25 Yuanan Diao

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

We compose the table of knots in the thickened torus T x I having diagrams with at most 4 crossings. The knots are constructed by the three-step process. First we list regular graphs of degree 4 with at most 4 vertices, then for each graph…

Geometric Topology · Mathematics 2012-07-02 A. A. Akimova , S. V. Matveev

We enumerate and show tables of minimal diagrams for all prime knots up to the triple-crossing number equal to five. We derive a minimal generating set of oriented moves connecting triple-crossing diagrams of the same oriented knot. We also…

Geometric Topology · Mathematics 2023-07-06 Michał Jabłonowski

We introduce a new combinatorial method to encode knots and links with applications to knot invariants. Clasp diagrams defined in this paper are combinatorial blueprints for building knot diagrams out of full twists on two strings rather…

Geometric Topology · Mathematics 2019-11-11 Jacob Mostovoy , Michael Polyak

We publish a table of primitive finite-type invariants of order less than or equal to six, for knots of ten or fewer crossings. We note certain mod-2 congruences, one of which leads to a chirality criterion in the Alexander polynomial. We…

Geometric Topology · Mathematics 2007-05-23 Ted Stanford

We introduce an unknotting-type number of knot projections that gives an upper bound of the crosscap number of knots. We determine the set of knot projections with the unknotting-type number at most two, and this result implies classical…

Geometric Topology · Mathematics 2020-08-26 Noboru Ito , Yusuke Takimura