概稳定一般Kneser超图的色数

IF 0.4 Q4 MATHEMATICS, APPLIED Journal of Combinatorics Pub Date : 2020-09-22 DOI:10.4310/joc.2022.v13.n3.a5
A. Jafari
{"title":"概稳定一般Kneser超图的色数","authors":"A. Jafari","doi":"10.4310/joc.2022.v13.n3.a5","DOIUrl":null,"url":null,"abstract":"Let $n\\ge 1$ and $s\\ge 1$ be integers. An almost $s$-stable subset $A$ of $[n]=\\{1,\\dots,n\\}$ is a subset such that for any two distinct elements $i, j\\in A$, one has $|i-j|\\ge s$. For a family $\\cal F$ of subsets in $[n]$ and $r\\ge 2$, the chromatic number of the $r$-uniform Kneser hypergraph $\\mbox{KG}^r({\\cal F})$, whose vertex set is $\\cal F$ and whose edges set is the set of $\\{A_1,\\dots, A_r\\}$ of pairwise disjoint elements of $\\cal F$, has been studied extensively in the literature and Abyazi Sani and Alishahi were able to give a lower bound for it in terms of the equatable $r$-colorability defect, $\\mbox{ecd}^r({\\cal F})$. In this article, the methods of Chen for the special family of all $k$-subsets of $[n]$, are modified to give lower bounds for the chromatic number of almost stable general Kneser hypergraph $\\mbox{KG}^r({\\cal F}_s)$ in terms of $\\mbox{ecd}^s({\\cal F})$. Here ${\\cal F}_s$ is he collection of almost $s$-stable elements of $\\cal F$. We also, propose a generalization of conjecture of Meunier.","PeriodicalId":44683,"journal":{"name":"Journal of Combinatorics","volume":"23 1","pages":""},"PeriodicalIF":0.4000,"publicationDate":"2020-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":"{\"title\":\"On the chromatic number of almost stable general Kneser hypergraphs\",\"authors\":\"A. Jafari\",\"doi\":\"10.4310/joc.2022.v13.n3.a5\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Let $n\\\\ge 1$ and $s\\\\ge 1$ be integers. An almost $s$-stable subset $A$ of $[n]=\\\\{1,\\\\dots,n\\\\}$ is a subset such that for any two distinct elements $i, j\\\\in A$, one has $|i-j|\\\\ge s$. For a family $\\\\cal F$ of subsets in $[n]$ and $r\\\\ge 2$, the chromatic number of the $r$-uniform Kneser hypergraph $\\\\mbox{KG}^r({\\\\cal F})$, whose vertex set is $\\\\cal F$ and whose edges set is the set of $\\\\{A_1,\\\\dots, A_r\\\\}$ of pairwise disjoint elements of $\\\\cal F$, has been studied extensively in the literature and Abyazi Sani and Alishahi were able to give a lower bound for it in terms of the equatable $r$-colorability defect, $\\\\mbox{ecd}^r({\\\\cal F})$. In this article, the methods of Chen for the special family of all $k$-subsets of $[n]$, are modified to give lower bounds for the chromatic number of almost stable general Kneser hypergraph $\\\\mbox{KG}^r({\\\\cal F}_s)$ in terms of $\\\\mbox{ecd}^s({\\\\cal F})$. Here ${\\\\cal F}_s$ is he collection of almost $s$-stable elements of $\\\\cal F$. We also, propose a generalization of conjecture of Meunier.\",\"PeriodicalId\":44683,\"journal\":{\"name\":\"Journal of Combinatorics\",\"volume\":\"23 1\",\"pages\":\"\"},\"PeriodicalIF\":0.4000,\"publicationDate\":\"2020-09-22\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"1\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Combinatorics\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.4310/joc.2022.v13.n3.a5\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"MATHEMATICS, APPLIED\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Combinatorics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.4310/joc.2022.v13.n3.a5","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"MATHEMATICS, APPLIED","Score":null,"Total":0}
引用次数: 1

摘要

设$n\ge 1$和$s\ge 1$为整数。$[n]=\{1,\dots,n\}$的一个几乎$s$稳定的子集$A$是这样一个子集:对于任意两个不同的元素$i, j\in A$,其中一个具有$|i-j|\ge s$。对于$[n]$和$r\ge 2$的子集$\cal F$,对于$r$ -均匀Kneser超图$\mbox{KG}^r({\cal F})$的色数,其顶点集为$\cal F$,其边集为$\cal F$的对向不相交元素的$\{A_1,\dots, A_r\}$的集合,已经在文献中得到了广泛的研究,Abyazi Sani和Alishahi能够根据可等价的$r$ -可色性缺陷给出它的下界。$\mbox{ecd}^r({\cal F})$。本文修正了关于$[n]$的所有$k$ -子集的特殊族的Chen方法,给出了关于$\mbox{ecd}^s({\cal F})$的概稳定一般Kneser超图$\mbox{KG}^r({\cal F}_s)$的色数的下界。这里${\cal F}_s$是$\cal F$中几乎$s$稳定元素的集合。我们还提出了对莫尼耶猜想的推广。
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 the chromatic number of almost stable general Kneser hypergraphs
Let $n\ge 1$ and $s\ge 1$ be integers. An almost $s$-stable subset $A$ of $[n]=\{1,\dots,n\}$ is a subset such that for any two distinct elements $i, j\in A$, one has $|i-j|\ge s$. For a family $\cal F$ of subsets in $[n]$ and $r\ge 2$, the chromatic number of the $r$-uniform Kneser hypergraph $\mbox{KG}^r({\cal F})$, whose vertex set is $\cal F$ and whose edges set is the set of $\{A_1,\dots, A_r\}$ of pairwise disjoint elements of $\cal F$, has been studied extensively in the literature and Abyazi Sani and Alishahi were able to give a lower bound for it in terms of the equatable $r$-colorability defect, $\mbox{ecd}^r({\cal F})$. In this article, the methods of Chen for the special family of all $k$-subsets of $[n]$, are modified to give lower bounds for the chromatic number of almost stable general Kneser hypergraph $\mbox{KG}^r({\cal F}_s)$ in terms of $\mbox{ecd}^s({\cal F})$. Here ${\cal F}_s$ is he collection of almost $s$-stable elements of $\cal F$. We also, propose a generalization of conjecture of Meunier.
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
Journal of Combinatorics
Journal of Combinatorics MATHEMATICS, APPLIED-
自引率
0.00%
发文量
21
期刊最新文献
Counting abelian squares efficiently for a problem in quantum computing On Mallows’ variation of the Stern–Brocot tree The chromatic number of squares of random graphs Approximation of Frankl’s conjecture in the complement family The weighted spectrum of the universal cover and an Alon–Boppana result for the normalized Laplacian
×
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