{"title":"Extending quasi-alternating links III","authors":"Kirandeep Kaur , Nafaa Chbili","doi":"10.1016/j.topol.2026.109736","DOIUrl":null,"url":null,"abstract":"<div><div>Champanerkar and Kofman <span><span>[1]</span></span> introduced a method for constructing quasi-alternating links by replacing a quasi-alternating crossing in a link diagram with a rational tangle of the same type. This approach, however, does not generally extend to alternating tangles of the opposite type or to non-alternating tangles.</div><div>In this paper, we identify sufficient conditions under which the construction remains valid when the crossing is replaced by an alternating rational tangle of opposite type. We also prove that this method applies to certain non-alternating pretzel tangles. As an application, we provide a table of non-alternating quasi-alternating knots with 13 crossings obtained using this construction. Additionally, we describe an infinite family of quasi-alternating links featuring a non-twisted quasi-alternating crossing that satisfies these sufficient conditions.</div></div>","PeriodicalId":51201,"journal":{"name":"Topology and its Applications","volume":"380 ","pages":"Article 109736"},"PeriodicalIF":0.5000,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Topology and its Applications","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S016686412600026X","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2026/1/16 0:00:00","PubModel":"Epub","JCR":"Q3","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
Abstract
Champanerkar and Kofman [1] introduced a method for constructing quasi-alternating links by replacing a quasi-alternating crossing in a link diagram with a rational tangle of the same type. This approach, however, does not generally extend to alternating tangles of the opposite type or to non-alternating tangles.
In this paper, we identify sufficient conditions under which the construction remains valid when the crossing is replaced by an alternating rational tangle of opposite type. We also prove that this method applies to certain non-alternating pretzel tangles. As an application, we provide a table of non-alternating quasi-alternating knots with 13 crossings obtained using this construction. Additionally, we describe an infinite family of quasi-alternating links featuring a non-twisted quasi-alternating crossing that satisfies these sufficient conditions.
期刊介绍:
Topology and its Applications is primarily concerned with publishing original research papers of moderate length. However, a limited number of carefully selected survey or expository papers are also included. The mathematical focus of the journal is that suggested by the title: Research in Topology. It is felt that it is inadvisable to attempt a definitive description of topology as understood for this journal. Certainly the subject includes the algebraic, general, geometric, and set-theoretic facets of topology as well as areas of interactions between topology and other mathematical disciplines, e.g. topological algebra, topological dynamics, functional analysis, category theory. Since the roles of various aspects of topology continue to change, the non-specific delineation of topics serves to reflect the current state of research in topology.
At regular intervals, the journal publishes a section entitled Open Problems in Topology, edited by J. van Mill and G.M. Reed. This is a status report on the 1100 problems listed in the book of the same name published by North-Holland in 1990, edited by van Mill and Reed.