On 2-Factors in r-Connected (K1, k, P4)-Free Graphs

Yoshimi Egawa, Jun Fujisawa, Shinya Fujita, Katsuhiro Ota

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

In [3], Faudree et al. considered the proposition “Every (X, Y)-free graph of sufficiently large order has a 2-factor,” and they determined those pairs (X, Y) which make this proposition true. Their result says that one of them is (X, Y) = (K1,4, P4). In this paper, we investigate the existence of 2-factors in r-connected (K1, k, P4)-free graphs. We prove that if r ≥ 1 and k ≥ 2, and if G is an r-connected (K1, k, P4)-free graph with minimum degree at least k − 1, then G has a 2-factor with at most max(k − r, 1) components unless (k − 1)K2 + (k − 2)K1 ⊆ G ⊆ (k − 1)K2 + Kk−2. The bound on the minimum degree is best possible.

Original languageEnglish
Pages (from-to)415-420
Number of pages6
JournalTokyo Journal of Mathematics
Volume31
Issue number2
DOIs
Publication statusPublished - 2008 Jan 1

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Minimum Degree
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Keywords

  • 2-factor
  • Forbidden subgraph
  • Minimum degree

ASJC Scopus subject areas

  • Mathematics(all)

Cite this

On 2-Factors in r-Connected (K1, k, P4)-Free Graphs. / Egawa, Yoshimi; Fujisawa, Jun; Fujita, Shinya; Ota, Katsuhiro.

In: Tokyo Journal of Mathematics, Vol. 31, No. 2, 01.01.2008, p. 415-420.

Research output: Contribution to journalArticle

Egawa, Yoshimi ; Fujisawa, Jun ; Fujita, Shinya ; Ota, Katsuhiro. / On 2-Factors in r-Connected (K1, k, P4)-Free Graphs. In: Tokyo Journal of Mathematics. 2008 ; Vol. 31, No. 2. pp. 415-420.
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