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Related papers: A conjecture on the Crazy Knight's Tour Problem

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Let $k,d,\lambda\geqslant1$ be integers with $d\geqslant\lambda $. Let $m(k,d,\lambda)$ be the maximum positive integer $n$ such that every set of $n$ points (not necessarily in general position) in $\mathbb{R}^{d}$ has the property that…

This paper introduces path triangulation of points in a bounded, simply connected surface region, replacing ordinary triangles in a Delaunay triangulation with path triangles from homotopy theory. A {\bf path triangle} has a border that is…

Algebraic Topology · Mathematics 2022-08-29 James F. Peters

In 1967, Klarner proposed a problem concerning the existence of reflecting $n$-queens configurations. The problem considers the feasibility of placing $n$ mutually non-attacking queens on the reflecting chessboard, an $n\times n$ chessboard…

Combinatorics · Mathematics 2025-08-20 Tantan Dai , Tom Kelly

New algorithms for generating closed knight's tours are obtained by generating a vertex-disjoint cycle cover of the knight's graph and joining the resulting cycles. It is shown experimentally that these algorithms are significantly faster…

Discrete Mathematics · Computer Science 2020-01-20 Ian Parberry

A whirling knight's tour is a Hamiltonian cycle in the digraph of counter-clockwise knight steps about the centre of an $n \times n$ board; its coil count $c$ is the winding number around the centre. We prove that no such tour with $c =…

Combinatorics · Mathematics 2026-05-12 Shisheng Li

We present a new problem called the incomplete Traveling Tournament problem, which introduces the well known Traveling Tournament Problem into the realm of incomplete round-robin tournaments. We focus on the case where teams can face each…

Optimization and Control · Mathematics 2026-03-23 Karel Devriesere , David Van Bulck , Dries Goossens

We study the existence and construction of circulant matrices $C$ of order $n\geq2$ with diagonal entries $d\geq0$, off-diagonal entries $\pm1$ and mutually orthogonal rows. These matrices generalize circulant conference ($d=0$) and…

Combinatorics · Mathematics 2019-02-05 Ondřej Turek , Dardo Goyeneche

Let $D$ be any elliptic right cylinder. We prove that every type of knot can be realized as the trajectory of a ball in $D.$ This proves a conjecture of Lamm and gives a new proof of a conjecture of Jones and Przytycki. We use Jacobi's…

Algebraic Geometry · Mathematics 2011-10-04 Daniel Pecker

Given $a,b,c\in\mathbb N$, let $D_{a,b,c}$ be the tournament on $a+b+c$ vertices obtained by replacing the vertices of the directed triangle $C_3$ with transitive tournaments $TT_a$, $TT_b$, and $TT_c$, respectively. Keevash and Sudakov…

Combinatorics · Mathematics 2026-03-24 Ming Chen , Wenxu Lu , Yun Wang , Zhiwei Zhang

The 1-2-3 conjecture has been solved positively in 2024 for finite graphs and by extension for infinite graphs which are locally finite. The solution is non-constructive, and finding explicit solutions for large (or infinite) graphs is very…

Combinatorics · Mathematics 2026-04-17 Alison Charlesworth , Christopher Ramsey , Nicolae Strungaru

The goal of this paper is twofold; first, show the equivalence between certain problems in geometry, such as view-obstruction and billiard ball motions, with the estimation of covering radii of lattice zonotopes. Second, we will estimate…

Metric Geometry · Mathematics 2020-05-04 Matthias Henze , Romanos-Diogenes Malikiosis

The present paper aims to extend the knight's tour problem for $k$-dimensional grids of the form $\{0,1\}^k$ to other fairy chess leapers. Accordingly, we constructively show the existence of closed tours in $2 \times 2 \times \cdots \times…

General Mathematics · Mathematics 2025-04-03 Gabriele Di Pietro , Marco Ripà

We give the first algorithmic study of a class of ``covering tour'' problems related to the geometric Traveling Salesman Problem: Find a polygonal tour for a cutter so that it sweeps out a specified region (``pocket''), in order to minimize…

Data Structures and Algorithms · Computer Science 2007-05-23 Esther M. Arkin , Michael A. Bender , Erik D. Demaine , Sandor P. Fekete , Joseph S. B. Mitchell , Saurabh Sethia

The Berge-Fulkerson conjecture states that every bridgeless cubic graph can be covered with six perfect matchings such that each edge is covered exactly twice. An equivalent reformulation is that it's possible to find a 6-cycle 4-cover. In…

Combinatorics · Mathematics 2026-03-25 Nikolay Ulyanov

In the order picking problem, a picker has to collect a number of products in a warehouse with a minimum length tour. Ratliff and Rosenthal gave a linear algorithm solving the order picking problem in the case where the warehouse has two…

Optimization and Control · Mathematics 2024-05-27 Paul Revenant , Hadrien Cambazard , Nicolas Catusse

Past studies of the billiard-ball paradox, a problem involving an object that travels back in time along a closed timelike curve (CTC), typically concern themselves with entirely classical histories, whereby any trajectorial effects…

Quantum Physics · Physics 2022-08-17 Lachlan G. Bishop , Timothy C. Ralph , Fabio Costa

We introduce two new metrics of "simplicity" for knight's tours: the number of turns and the number of crossings. We give a novel algorithm that produces tours with $9.25n+O(1)$ turns and $12n+O(1)$ crossings on an $n\times n$ board, and we…

Data Structures and Algorithms · Computer Science 2022-01-19 Juan Jose Besa , Timothy Johnson , Nil Mamano , Martha C. Osegueda , Parker Williams

We investigate a variety of problems of finding tours and cycle covers with minimum turn cost. Questions of this type have been studied in the past, with complexity and approximation results as well as open problems dating back to work by…

Computational Geometry · Computer Science 2019-04-26 Sándor P. Fekete , Dominik Krupke

Finding unambiguous diagrammatic representations for first-order logical formulas and relational queries with arbitrarily nested disjunctions has been a surprisingly long-standing unsolved problem. We refer to this problem as the…

Databases · Computer Science 2024-12-12 Wolfgang Gatterbauer

In this paper, we consider the $k$-Covering Canadian Traveller Problem ($k$-CCTP), which can be seen as a variant of the Travelling Salesperson Problem. The goal of $k$-CCTP is finding the shortest tour for a traveller to visit a set of…

Data Structures and Algorithms · Computer Science 2023-04-28 Niklas Hahn , Michalis Xefteris