避开顶点的连线和可移动路径

IF 1.2 1区 数学 Q1 MATHEMATICS
Xiying Du, Yanjia Li, Shijie Xie , Xingxing Yu
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引用次数: 0

摘要

如果对于 G 中任何不同的顶点 a1,...,am,b1,b2,存在 G 的互不相交的连通子图 A,B,使得 a1,...,am∈V(A)和 b1,b2∈V(B),则图 G 是 (2,m)-linked 的。结构图理论的一个基本结果是(2,2)连接图的特征描述。要描述 m≥3 的 (2,m) 链接图似乎很难。本文提供了 (2,m) 链接图的部分特征。这意味着每个 (2m+2)-linkected graphs G 都是 (2,m)-linked 的,并且对于 G 的任何不同顶点 a1,...,am,b1,b2,G 中都存在一条路径 P,该路径 P 位于 b1 和 b2 之间,并避开 {a1,...,am},这样 G-P 就是连通的,从而改善了之前 10m 的连通性约束。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
Linkages and removable paths avoiding vertices

A graph G is (2,m)-linked if, for any distinct vertices a1,,am,b1,b2 in G, there exist disjoint connected subgraphs A,B of G such that a1,,amV(A) and b1,b2V(B). A fundamental result in structural graph theory is the characterization of (2,2)-linked graphs. It appears to be difficult to characterize (2,m)-linked graphs for m3. In this paper, we provide a partial characterization of (2,m)-linked graphs. This implies that every (2m+2)-connected graphs G is (2,m)-linked and for any distinct vertices a1,,am,b1,b2 of G, there is a path P in G between b1 and b2 and avoiding {a1,,am} such that GP is connected, improving a previous connectivity bound of 10m.

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来源期刊
CiteScore
2.70
自引率
14.30%
发文量
99
审稿时长
6-12 weeks
期刊介绍: The Journal of Combinatorial Theory publishes original mathematical research dealing with theoretical and physical aspects of the study of finite and discrete structures in all branches of science. Series B is concerned primarily with graph theory and matroid theory and is a valuable tool for mathematicians and computer scientists.
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