H. Galeana-Sánchez, R. Rojas-Monroy, Maria Del Rocio Sanchez Lopez, Berta Zavala-Santana
{"title":"$H$-核在细分有向图中行走","authors":"H. Galeana-Sánchez, R. Rojas-Monroy, Maria Del Rocio Sanchez Lopez, Berta Zavala-Santana","doi":"10.22108/TOC.2020.107875.1529","DOIUrl":null,"url":null,"abstract":"Let $H$ be a digraph possibly with loops and $D$ a digraph without loops whose arcs are colored with the vertices of $H$ ($D$ is said to be an $H$-colored digraph). A directed walk $W$ in $D$ is said to be an $H$-walk if and only if the consecutive colors encountered on $W$ form a directed walk in $H$. A subset $N$ of the vertices of $D$ is said to be an $H$-kernel by walks if (1) for every pair of different vertices in $N$ there is no $H$-walk between them ($N$ is $H$-independent by walks) and (2) for each vertex $u$ in $V$($D$)-$N$ there exists an $H$-walk from $u$ to $N$ in $D$ ($N$ is $H$-absorbent by walks). Suppose that $D$ is a digraph possibly infinite. In this paper we will work with the subdivision digraph $S_H$($D$) of $D$, where $S_H$($D$) is an $H$-colored digraph defined as follows: $V$($S_H$($D$)) = $V$($D$) $cup$ $A$($D$) and $A$($S_H$($D$)) = {($u$,$a$) : $a$ = ($u$,$v$) $in$ $A$($D$)} $cup$ {($a$,$v$) : $a$ = ($u$,$v$) $in$ $A$($D$)}, where ($u$, $a$, $v$) is an $H$-walk in $S_H$($D$) for every $a$ = ($u$,$v$) in $A$($D$). We will show sufficient conditions on $D$ and on $S_H$($D$) which guarantee the existence or uniqueness of $H$-kernels by walks in $S_H$($D$).","PeriodicalId":43837,"journal":{"name":"Transactions on Combinatorics","volume":"9 1","pages":"61-75"},"PeriodicalIF":0.6000,"publicationDate":"2020-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":"{\"title\":\"$H$-kernels by walks in subdivision digraph\",\"authors\":\"H. Galeana-Sánchez, R. Rojas-Monroy, Maria Del Rocio Sanchez Lopez, Berta Zavala-Santana\",\"doi\":\"10.22108/TOC.2020.107875.1529\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Let $H$ be a digraph possibly with loops and $D$ a digraph without loops whose arcs are colored with the vertices of $H$ ($D$ is said to be an $H$-colored digraph). A directed walk $W$ in $D$ is said to be an $H$-walk if and only if the consecutive colors encountered on $W$ form a directed walk in $H$. A subset $N$ of the vertices of $D$ is said to be an $H$-kernel by walks if (1) for every pair of different vertices in $N$ there is no $H$-walk between them ($N$ is $H$-independent by walks) and (2) for each vertex $u$ in $V$($D$)-$N$ there exists an $H$-walk from $u$ to $N$ in $D$ ($N$ is $H$-absorbent by walks). Suppose that $D$ is a digraph possibly infinite. In this paper we will work with the subdivision digraph $S_H$($D$) of $D$, where $S_H$($D$) is an $H$-colored digraph defined as follows: $V$($S_H$($D$)) = $V$($D$) $cup$ $A$($D$) and $A$($S_H$($D$)) = {($u$,$a$) : $a$ = ($u$,$v$) $in$ $A$($D$)} $cup$ {($a$,$v$) : $a$ = ($u$,$v$) $in$ $A$($D$)}, where ($u$, $a$, $v$) is an $H$-walk in $S_H$($D$) for every $a$ = ($u$,$v$) in $A$($D$). We will show sufficient conditions on $D$ and on $S_H$($D$) which guarantee the existence or uniqueness of $H$-kernels by walks in $S_H$($D$).\",\"PeriodicalId\":43837,\"journal\":{\"name\":\"Transactions on Combinatorics\",\"volume\":\"9 1\",\"pages\":\"61-75\"},\"PeriodicalIF\":0.6000,\"publicationDate\":\"2020-01-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"1\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Transactions on Combinatorics\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.22108/TOC.2020.107875.1529\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Transactions on Combinatorics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.22108/TOC.2020.107875.1529","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 1
摘要
设$H$是一个可能有圈的有向图,$D$是一个没有圈的有向图,其弧线用$H$的顶点着色($D$被称为$H$着色的有向图)。$D$中的有向行走$W$被称为$H$-行走当且仅当$W$上遇到的连续颜色形成$H$的有向行走。$D$的顶点子集$N$被称为$H$-游动核,如果(1)对于$N$中的每一对不同的顶点,它们之间没有$H$-游动($N$是$H$-游动独立的),并且(2)对于$V$($D$)中的每个顶点$u$ -$N$存在$H$-游动从$u$到$D$ ($N$是$H$-游动吸收)。假设$D$是有向图,可能是无限的。在本文中,我们将与细分有向图S_H (D)美元美元D,美元,S_H美元($ D $)是一种H的美元有向图定义如下:V美元(S_H (D)美元美元)= V (D)美元美元杯美元美元(D)美元和美元美元(S_H (D)美元美元)= {(u,美元美元美元):$ $ = (u美元,美元V $)在$ $美元(D)美元}$杯${(美元,美元V $):$ $ = (u美元,美元V $)在$ $美元(D)美元},,(u,美元美元美元,V)美元是一个H走美元S_H (D)美元美元每一个美元= (u美元,美元V $)在一个美元($ D $)。我们将给出$D$和$S_H$($D$)上的充分条件,通过$S_H$($D$)的遍历来保证$H$-核的存在或唯一性。
Let $H$ be a digraph possibly with loops and $D$ a digraph without loops whose arcs are colored with the vertices of $H$ ($D$ is said to be an $H$-colored digraph). A directed walk $W$ in $D$ is said to be an $H$-walk if and only if the consecutive colors encountered on $W$ form a directed walk in $H$. A subset $N$ of the vertices of $D$ is said to be an $H$-kernel by walks if (1) for every pair of different vertices in $N$ there is no $H$-walk between them ($N$ is $H$-independent by walks) and (2) for each vertex $u$ in $V$($D$)-$N$ there exists an $H$-walk from $u$ to $N$ in $D$ ($N$ is $H$-absorbent by walks). Suppose that $D$ is a digraph possibly infinite. In this paper we will work with the subdivision digraph $S_H$($D$) of $D$, where $S_H$($D$) is an $H$-colored digraph defined as follows: $V$($S_H$($D$)) = $V$($D$) $cup$ $A$($D$) and $A$($S_H$($D$)) = {($u$,$a$) : $a$ = ($u$,$v$) $in$ $A$($D$)} $cup$ {($a$,$v$) : $a$ = ($u$,$v$) $in$ $A$($D$)}, where ($u$, $a$, $v$) is an $H$-walk in $S_H$($D$) for every $a$ = ($u$,$v$) in $A$($D$). We will show sufficient conditions on $D$ and on $S_H$($D$) which guarantee the existence or uniqueness of $H$-kernels by walks in $S_H$($D$).