图的同源线性商和边沿理想

IF 0.6 4区 数学 Q3 MATHEMATICS
NADIA TAGHIPOUR, SHAMILA BAYATI, FARHAD RAHMATI
{"title":"图的同源线性商和边沿理想","authors":"NADIA TAGHIPOUR, SHAMILA BAYATI, FARHAD RAHMATI","doi":"10.1017/s0004972723001363","DOIUrl":null,"url":null,"abstract":"It is well known that the edge ideal <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0004972723001363_inline1.png\" /> <jats:tex-math> $I(G)$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> of a simple graph <jats:italic>G</jats:italic> has linear quotients if and only if <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0004972723001363_inline2.png\" /> <jats:tex-math> $G^c$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> is chordal. We investigate when the property of having linear quotients is inherited by homological shift ideals of an edge ideal. We will see that adding a cluster to the graph <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0004972723001363_inline3.png\" /> <jats:tex-math> $G^c$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> when <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0004972723001363_inline4.png\" /> <jats:tex-math> $I(G)$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> has homological linear quotients results in a graph with the same property. In particular, <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0004972723001363_inline5.png\" /> <jats:tex-math> $I(G)$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> has homological linear quotients when <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0004972723001363_inline6.png\" /> <jats:tex-math> $G^c$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> is a block graph. We also show that adding pinnacles to trees preserves the property of having homological linear quotients for the edge ideal of their complements. Furthermore, <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0004972723001363_inline7.png\" /> <jats:tex-math> $I(G)$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> has homological linear quotients for every graph <jats:italic>G</jats:italic> such that <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0004972723001363_inline8.png\" /> <jats:tex-math> $G^c$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> is a <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0004972723001363_inline9.png\" /> <jats:tex-math> $\\lambda $ </jats:tex-math> </jats:alternatives> </jats:inline-formula>-minimal chordal graph.","PeriodicalId":50720,"journal":{"name":"Bulletin of the Australian Mathematical Society","volume":null,"pages":null},"PeriodicalIF":0.6000,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"HOMOLOGICAL LINEAR QUOTIENTS AND EDGE IDEALS OF GRAPHS\",\"authors\":\"NADIA TAGHIPOUR, SHAMILA BAYATI, FARHAD RAHMATI\",\"doi\":\"10.1017/s0004972723001363\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"It is well known that the edge ideal <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\\\"http://www.w3.org/1999/xlink\\\" mime-subtype=\\\"png\\\" xlink:href=\\\"S0004972723001363_inline1.png\\\" /> <jats:tex-math> $I(G)$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> of a simple graph <jats:italic>G</jats:italic> has linear quotients if and only if <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\\\"http://www.w3.org/1999/xlink\\\" mime-subtype=\\\"png\\\" xlink:href=\\\"S0004972723001363_inline2.png\\\" /> <jats:tex-math> $G^c$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> is chordal. We investigate when the property of having linear quotients is inherited by homological shift ideals of an edge ideal. We will see that adding a cluster to the graph <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\\\"http://www.w3.org/1999/xlink\\\" mime-subtype=\\\"png\\\" xlink:href=\\\"S0004972723001363_inline3.png\\\" /> <jats:tex-math> $G^c$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> when <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\\\"http://www.w3.org/1999/xlink\\\" mime-subtype=\\\"png\\\" xlink:href=\\\"S0004972723001363_inline4.png\\\" /> <jats:tex-math> $I(G)$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> has homological linear quotients results in a graph with the same property. In particular, <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\\\"http://www.w3.org/1999/xlink\\\" mime-subtype=\\\"png\\\" xlink:href=\\\"S0004972723001363_inline5.png\\\" /> <jats:tex-math> $I(G)$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> has homological linear quotients when <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\\\"http://www.w3.org/1999/xlink\\\" mime-subtype=\\\"png\\\" xlink:href=\\\"S0004972723001363_inline6.png\\\" /> <jats:tex-math> $G^c$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> is a block graph. We also show that adding pinnacles to trees preserves the property of having homological linear quotients for the edge ideal of their complements. Furthermore, <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\\\"http://www.w3.org/1999/xlink\\\" mime-subtype=\\\"png\\\" xlink:href=\\\"S0004972723001363_inline7.png\\\" /> <jats:tex-math> $I(G)$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> has homological linear quotients for every graph <jats:italic>G</jats:italic> such that <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\\\"http://www.w3.org/1999/xlink\\\" mime-subtype=\\\"png\\\" xlink:href=\\\"S0004972723001363_inline8.png\\\" /> <jats:tex-math> $G^c$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> is a <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\\\"http://www.w3.org/1999/xlink\\\" mime-subtype=\\\"png\\\" xlink:href=\\\"S0004972723001363_inline9.png\\\" /> <jats:tex-math> $\\\\lambda $ </jats:tex-math> </jats:alternatives> </jats:inline-formula>-minimal chordal graph.\",\"PeriodicalId\":50720,\"journal\":{\"name\":\"Bulletin of the Australian Mathematical Society\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.6000,\"publicationDate\":\"2024-01-29\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Bulletin of the Australian Mathematical Society\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://doi.org/10.1017/s0004972723001363\",\"RegionNum\":4,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Bulletin of the Australian Mathematical Society","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1017/s0004972723001363","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0

摘要

众所周知,简单图 G 的边理想 $I(G)$ 具有线性商,当且仅当 $G^c$ 是弦性的。我们将研究边理想的同调移动理想何时继承了线性商的性质。我们将看到,当 $I(G)$ 具有同调线性商时,给图 $G^c$ 添加一个簇会得到具有相同性质的图。特别是,当 $G^c$ 是块图时,$I(G)$ 具有同调线性商。我们还证明,将尖顶添加到树中会保留其补集的边理想具有同调线性商的特性。此外,$I(G)$ 对每个图 G 都有同调线性商,这样 $G^c$ 就是一个 $\lambda $ 最小弦图。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
HOMOLOGICAL LINEAR QUOTIENTS AND EDGE IDEALS OF GRAPHS
It is well known that the edge ideal $I(G)$ of a simple graph G has linear quotients if and only if $G^c$ is chordal. We investigate when the property of having linear quotients is inherited by homological shift ideals of an edge ideal. We will see that adding a cluster to the graph $G^c$ when $I(G)$ has homological linear quotients results in a graph with the same property. In particular, $I(G)$ has homological linear quotients when $G^c$ is a block graph. We also show that adding pinnacles to trees preserves the property of having homological linear quotients for the edge ideal of their complements. Furthermore, $I(G)$ has homological linear quotients for every graph G such that $G^c$ is a $\lambda $ -minimal chordal graph.
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
CiteScore
1.20
自引率
14.30%
发文量
149
审稿时长
4-8 weeks
期刊介绍: Bulletin of the Australian Mathematical Society aims at quick publication of original research in all branches of mathematics. Papers are accepted only after peer review but editorial decisions on acceptance or otherwise are taken quickly, normally within a month of receipt of the paper. The Bulletin concentrates on presenting new and interesting results in a clear and attractive way. Published Bi-monthly Published for the Australian Mathematical Society
×
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
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
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 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信