Characterizing forbidden pairs for the existence of even factors

IF 0.7 3区数学 Q2 MATHEMATICS

Discrete Mathematics Pub Date : 2025-01-03 DOI:10.1016/j.disc.2024.114384

Lei Zhang , Liming Xiong

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引用次数: 0

Abstract

Let

H

be a class of given graphs. We say that a graph is

H

f r e e

if it contains no induced subgraph isomorphic to H for every

H \in H

. 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) \geq 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) \geq 2

and every odd branch-bond of G has an edge branch.

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来源期刊

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.