论小属曲面中 1- 嵌入图的受限匹配扩展

IF 0.7 3区 数学 Q2 MATHEMATICS Discrete Mathematics Pub Date : 2024-07-22 DOI:10.1016/j.disc.2024.114172
{"title":"论小属曲面中 1- 嵌入图的受限匹配扩展","authors":"","doi":"10.1016/j.disc.2024.114172","DOIUrl":null,"url":null,"abstract":"<div><p>Let <em>G</em> be a connected graph with at least <span><math><mn>2</mn><mo>(</mo><mi>m</mi><mo>+</mo><mi>n</mi><mo>+</mo><mn>1</mn><mo>)</mo></math></span> vertices that contains a perfect matching. Then <em>G</em> is <span><math><mi>E</mi><mo>(</mo><mi>m</mi><mo>,</mo><mi>n</mi><mo>)</mo></math></span> if for each pair of disjoint matchings <span><math><mi>M</mi><mo>,</mo><mi>N</mi><mo>⊆</mo><mi>E</mi><mo>(</mo><mi>G</mi><mo>)</mo></math></span> of size <em>m</em> and <em>n</em>, respectively, there exists a perfect matching <em>F</em> in <em>G</em> such that <span><math><mi>M</mi><mo>⊆</mo><mi>F</mi></math></span> and <span><math><mi>F</mi><mo>∩</mo><mi>N</mi><mo>=</mo><mo>∅</mo></math></span>. A graph <em>G</em> is <em>1-embeddable</em> in a surface Σ if <em>G</em> can be drawn in Σ so that every edge of <em>G</em> crosses at most one other edge at a point. R.E.L. Aldred and M.D. Plummer <span><span>[1]</span></span>, <span><span>[2]</span></span> investigated the properties <span><math><mi>E</mi><mo>(</mo><mi>m</mi><mo>,</mo><mi>n</mi><mo>)</mo></math></span> for graphs embedded in the plane, torus, projective plane and Klein bottle. In this paper, we study the property <span><math><mi>E</mi><mo>(</mo><mi>m</mi><mo>,</mo><mi>n</mi><mo>)</mo></math></span> for 1-embeddable graphs in surfaces with small genus. It is shown that no 1-embeddable graph in the plane or projective plane is <span><math><mi>E</mi><mo>(</mo><mn>4</mn><mo>,</mo><mn>1</mn><mo>)</mo></math></span> and no 1-embeddable graph in the torus or Klein bottle is <span><math><mi>E</mi><mo>(</mo><mn>5</mn><mo>,</mo><mn>1</mn><mo>)</mo></math></span>. As corollaries, no 1-embeddable graph in the plane or projective plane is 5-extendable and no 1-embeddable graph in the torus or Klein bottle is 6-extendable. Some examples show that such results are best possible.</p></div>","PeriodicalId":50572,"journal":{"name":"Discrete Mathematics","volume":null,"pages":null},"PeriodicalIF":0.7000,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"On restricted matching extension of 1-embeddable graphs in surfaces with small genus\",\"authors\":\"\",\"doi\":\"10.1016/j.disc.2024.114172\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Let <em>G</em> be a connected graph with at least <span><math><mn>2</mn><mo>(</mo><mi>m</mi><mo>+</mo><mi>n</mi><mo>+</mo><mn>1</mn><mo>)</mo></math></span> vertices that contains a perfect matching. Then <em>G</em> is <span><math><mi>E</mi><mo>(</mo><mi>m</mi><mo>,</mo><mi>n</mi><mo>)</mo></math></span> if for each pair of disjoint matchings <span><math><mi>M</mi><mo>,</mo><mi>N</mi><mo>⊆</mo><mi>E</mi><mo>(</mo><mi>G</mi><mo>)</mo></math></span> of size <em>m</em> and <em>n</em>, respectively, there exists a perfect matching <em>F</em> in <em>G</em> such that <span><math><mi>M</mi><mo>⊆</mo><mi>F</mi></math></span> and <span><math><mi>F</mi><mo>∩</mo><mi>N</mi><mo>=</mo><mo>∅</mo></math></span>. A graph <em>G</em> is <em>1-embeddable</em> in a surface Σ if <em>G</em> can be drawn in Σ so that every edge of <em>G</em> crosses at most one other edge at a point. R.E.L. Aldred and M.D. Plummer <span><span>[1]</span></span>, <span><span>[2]</span></span> investigated the properties <span><math><mi>E</mi><mo>(</mo><mi>m</mi><mo>,</mo><mi>n</mi><mo>)</mo></math></span> for graphs embedded in the plane, torus, projective plane and Klein bottle. In this paper, we study the property <span><math><mi>E</mi><mo>(</mo><mi>m</mi><mo>,</mo><mi>n</mi><mo>)</mo></math></span> for 1-embeddable graphs in surfaces with small genus. It is shown that no 1-embeddable graph in the plane or projective plane is <span><math><mi>E</mi><mo>(</mo><mn>4</mn><mo>,</mo><mn>1</mn><mo>)</mo></math></span> and no 1-embeddable graph in the torus or Klein bottle is <span><math><mi>E</mi><mo>(</mo><mn>5</mn><mo>,</mo><mn>1</mn><mo>)</mo></math></span>. As corollaries, no 1-embeddable graph in the plane or projective plane is 5-extendable and no 1-embeddable graph in the torus or Klein bottle is 6-extendable. Some examples show that such results are best possible.</p></div>\",\"PeriodicalId\":50572,\"journal\":{\"name\":\"Discrete Mathematics\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.7000,\"publicationDate\":\"2024-07-22\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Discrete Mathematics\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0012365X24003030\",\"RegionNum\":3,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Discrete Mathematics","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0012365X24003030","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0

摘要

设 是一个至少有顶点的连通图,且包含一个完美匹配。那么,对于每一对大小分别为 和 的不相邻匹配,都存在一个完美匹配,使得 和 。如果可以在 Σ 中画出一条边,使得每条边最多与另一条边相交于一点,则该图位于曲面 Σ 中。R.E.L. Aldred 和 M.D. Plummer 研究了嵌入平面、环面、投影面和克莱因瓶中的图的性质。在本文中,我们研究了小属的曲面中 1-embeddable 图形的性质。结果表明,平面或投影面中没有 1-embeddable 图形,环面或克莱因瓶中也没有 1-embeddable 图形。作为推论,平面或投影面中没有 1- 嵌入图是 5- 可扩展的,环面或克莱因瓶中没有 1- 嵌入图是 6- 可扩展的。一些例子表明,这样的结果是最有可能的。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
查看原文
分享 分享
微信好友 朋友圈 QQ好友 复制链接
本刊更多论文
On restricted matching extension of 1-embeddable graphs in surfaces with small genus

Let G be a connected graph with at least 2(m+n+1) vertices that contains a perfect matching. Then G is E(m,n) if for each pair of disjoint matchings M,NE(G) of size m and n, respectively, there exists a perfect matching F in G such that MF and FN=. A graph G is 1-embeddable in a surface Σ if G can be drawn in Σ so that every edge of G crosses at most one other edge at a point. R.E.L. Aldred and M.D. Plummer [1], [2] investigated the properties E(m,n) for graphs embedded in the plane, torus, projective plane and Klein bottle. In this paper, we study the property E(m,n) for 1-embeddable graphs in surfaces with small genus. It is shown that no 1-embeddable graph in the plane or projective plane is E(4,1) and no 1-embeddable graph in the torus or Klein bottle is E(5,1). As corollaries, no 1-embeddable graph in the plane or projective plane is 5-extendable and no 1-embeddable graph in the torus or Klein bottle is 6-extendable. Some examples show that such results are best possible.

求助全文
通过发布文献求助,成功后即可免费获取论文全文。 去求助
来源期刊
Discrete Mathematics
Discrete Mathematics 数学-数学
CiteScore
1.50
自引率
12.50%
发文量
424
审稿时长
6 months
期刊介绍: Discrete Mathematics provides a common forum for significant research in many areas of discrete mathematics and combinatorics. Among the fields covered by Discrete Mathematics are graph and hypergraph theory, enumeration, coding theory, block designs, the combinatorics of partially ordered sets, extremal set theory, matroid theory, algebraic combinatorics, discrete geometry, matrices, and discrete probability theory. Items in the journal include research articles (Contributions or Notes, depending on length) and survey/expository articles (Perspectives). Efforts are made to process the submission of Notes (short articles) quickly. The Perspectives section features expository articles accessible to a broad audience that cast new light or present unifying points of view on well-known or insufficiently-known topics.
期刊最新文献
On graphs with maximum difference between game chromatic number and chromatic number Stabbing boxes with finitely many axis-parallel lines and flats Transversal coalitions in hypergraphs Fibonacci and Catalan paths in a wall On the inclusion chromatic index of a Halin graph
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
已复制链接
已复制链接
快去分享给好友吧!
我知道了
×
扫码分享
扫码分享
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1