{"title":"Chains, Koch Chains, and Point Sets with Many Triangulations","authors":"Daniel Rutschmann, Manuel Wettstein","doi":"https://dl.acm.org/doi/10.1145/3585535","DOIUrl":null,"url":null,"abstract":"<p>We introduce the abstract notion of a chain, which is a sequence of <i>n</i> points in the plane, ordered by <i>x</i>-coordinates, so that the edge between any two consecutive points is unavoidable as far as triangulations are concerned. A general theory of the structural properties of chains is developed, alongside a general understanding of their number of triangulations.</p><p>We also describe an intriguing new and concrete configuration, which we call the Koch chain due to its similarities to the Koch curve. A specific construction based on Koch chains is then shown to have Ω (9.08<sup><i>n</i></sup>) triangulations. This is a significant improvement over the previous and long-standing lower bound of Ω (8.65<sup><i>n</i></sup>) for the maximum number of triangulations of planar point sets.</p>","PeriodicalId":50022,"journal":{"name":"Journal of the ACM","volume":"27 1","pages":""},"PeriodicalIF":2.3000,"publicationDate":"2023-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of the ACM","FirstCategoryId":"94","ListUrlMain":"https://doi.org/https://dl.acm.org/doi/10.1145/3585535","RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"COMPUTER SCIENCE, HARDWARE & ARCHITECTURE","Score":null,"Total":0}
引用次数: 0
Abstract
We introduce the abstract notion of a chain, which is a sequence of n points in the plane, ordered by x-coordinates, so that the edge between any two consecutive points is unavoidable as far as triangulations are concerned. A general theory of the structural properties of chains is developed, alongside a general understanding of their number of triangulations.
We also describe an intriguing new and concrete configuration, which we call the Koch chain due to its similarities to the Koch curve. A specific construction based on Koch chains is then shown to have Ω (9.08n) triangulations. This is a significant improvement over the previous and long-standing lower bound of Ω (8.65n) for the maximum number of triangulations of planar point sets.
期刊介绍:
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