Proof of a conjecture on connectivity keeping odd paths in k-connected bipartite graphs

IF 0.7 3区 数学 Q2 MATHEMATICS
Qing Yang, Yingzhi Tian
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引用次数: 0

Abstract

Luo, Tian and Wu (2022) conjectured that for any tree T with bipartition X and Y, every k-connected bipartite graph G with minimum degree at least k+t, where t=max{|X|,|Y|}, contains a tree TT such that GV(T) is still k-connected. Note that t=m2 when the tree T is the path with order m. In this paper, we prove that every k-connected bipartite graph G with minimum degree at least k+m+12 contains a path P of order m such that GV(P) remains k-connected. This shows that the conjecture is true for paths with odd order. For paths with even order, the minimum degree bound in this paper is the bound in the conjecture plus one.
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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.
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