An Improvement of the Lower Bound on the Minimum Number of ≤<i>k</i>-Edges
In this paper, we improve the lower bound on the minimum number of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo> </mo><mo>≤</mo><mi>k</mi></mrow></semant...
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MDPI AG
2021-03-01
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Online Access: | https://www.mdpi.com/2227-7390/9/5/525 |
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author | Javier Rodrigo Susana Merchán Danilo Magistrali Mariló López |
author_facet | Javier Rodrigo Susana Merchán Danilo Magistrali Mariló López |
author_sort | Javier Rodrigo |
collection | DOAJ |
description | In this paper, we improve the lower bound on the minimum number of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo> </mo><mo>≤</mo><mi>k</mi></mrow></semantics></math></inline-formula>-edges in sets of <i>n</i> points in general position in the plane when <i>k</i> is close to <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mfrac><mi>n</mi><mn>2</mn></mfrac></semantics></math></inline-formula>. As a consequence, we improve the current best lower bound of the rectilinear crossing number of the complete graph <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>K</mi><mi>n</mi></msub></semantics></math></inline-formula> for some values of <i>n</i>. |
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issn | 2227-7390 |
language | English |
last_indexed | 2024-03-09T05:47:56Z |
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spelling | doaj.art-2f78f3c2b6304f8fbb7d2681f8f8eb782023-12-03T12:19:12ZengMDPI AGMathematics2227-73902021-03-019552510.3390/math9050525An Improvement of the Lower Bound on the Minimum Number of ≤<i>k</i>-EdgesJavier Rodrigo0Susana Merchán1Danilo Magistrali2Mariló López3Departamento de Matemática Aplicada, E.T.S.I. Universidad Pontificia Comillas, Alberto Aguilera 25, 28015 Madrid, SpainDepartamento de Matemática e Informática Aplicadas a las Ingenierías Civil y Naval, Escuela de Caminos, Canales y Puertos, Universidad Politécnica de Madrid, Profesor Aranguren, 3, 28040 Madrid, SpainDepartamento de Matemática Aplicada, E.T.S.I. Universidad Pontificia Comillas, Alberto Aguilera 25, 28015 Madrid, SpainDepartamento de Matemática e Informática Aplicadas a las Ingenierías Civil y Naval, Escuela de Caminos, Canales y Puertos, Universidad Politécnica de Madrid, Profesor Aranguren, 3, 28040 Madrid, SpainIn this paper, we improve the lower bound on the minimum number of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo> </mo><mo>≤</mo><mi>k</mi></mrow></semantics></math></inline-formula>-edges in sets of <i>n</i> points in general position in the plane when <i>k</i> is close to <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mfrac><mi>n</mi><mn>2</mn></mfrac></semantics></math></inline-formula>. As a consequence, we improve the current best lower bound of the rectilinear crossing number of the complete graph <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>K</mi><mi>n</mi></msub></semantics></math></inline-formula> for some values of <i>n</i>.https://www.mdpi.com/2227-7390/9/5/525combinatorial geometry≤k-edgesrectilinear crossing numberoptimizationcomplete graphs |
spellingShingle | Javier Rodrigo Susana Merchán Danilo Magistrali Mariló López An Improvement of the Lower Bound on the Minimum Number of ≤<i>k</i>-Edges Mathematics combinatorial geometry ≤k-edges rectilinear crossing number optimization complete graphs |
title | An Improvement of the Lower Bound on the Minimum Number of ≤<i>k</i>-Edges |
title_full | An Improvement of the Lower Bound on the Minimum Number of ≤<i>k</i>-Edges |
title_fullStr | An Improvement of the Lower Bound on the Minimum Number of ≤<i>k</i>-Edges |
title_full_unstemmed | An Improvement of the Lower Bound on the Minimum Number of ≤<i>k</i>-Edges |
title_short | An Improvement of the Lower Bound on the Minimum Number of ≤<i>k</i>-Edges |
title_sort | improvement of the lower bound on the minimum number of ≤ i k i edges |
topic | combinatorial geometry ≤k-edges rectilinear crossing number optimization complete graphs |
url | https://www.mdpi.com/2227-7390/9/5/525 |
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