偶因子存在的禁忌对的表征

IF 0.7 3区 数学 Q2 MATHEMATICS Discrete Mathematics Pub Date : 2025-04-01 Epub Date: 2025-01-03 DOI:10.1016/j.disc.2024.114384
Lei Zhang , Liming Xiong
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引用次数: 0

摘要

设H是一类给定的图。如果一个图对于每一个H∈H不包含与H同构的诱导子图,我们说它是无H的。2017年,第二作者刻画了至少三阶的所有连通图H,使得每个无H图G都有偶因子当且仅当δ(G)≥2,并且G的每个奇支键都有一个边分支。本文考虑了H是不连通的情况,并刻画了连通图的所有对{R,S},使得每一个{R,S}自由图G有偶因子当且仅当δ(G)≥2,且G的每一个奇支键都有一个边分支。
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Characterizing forbidden pairs for the existence of even factors
Let H be a class of given graphs. We say that a graph is H-free if it contains no induced subgraph isomorphic to H for every HH. In 2017, the second author characterized all connected graphs H with order at least three such that every H-free graph G has an even factor if and only if δ(G)2 and every odd branch-bond of G has an edge branch. In this paper, we consider the case H is disconnected and characterize all the pairs {R,S} of connected graphs such that every {R,S}-free graph G has an even factor if and only if δ(G)2 and every odd branch-bond of G has an edge branch.
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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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