Discussiones
Mathematicae Graph Theory 20(2) (2000) 165-172
DOI: https://doi.org/10.7151/dmgt.1116
2-FACTORS IN CLAW-FREE GRAPHS
Guantao Chen Georgia State University, Atlanta, GA 30303 |
Jill R. Faudree University of Alaska Fairbanks, Fairbanks, AK 99775 |
Ronald J. Gould Emory University, Atlanta, GA 30322 |
Akira Saito Nihon University, Tokyo 156, Japan |
Abstract
We consider the question of the range of the number of cycles possible in a 2-factor of a 2-connected claw-free graph with sufficiently high minimum degree. (By claw-free we mean the graph has no induced K1,3.) In particular, we show that for such a graph G of order n ≥ 51 with δ(G) ≥ [(n−2)/3], G contains a 2-factor with exactly k cycles, for 1 ≤ k ≤ [(n−24)/3]. We also show that this result is sharp in the sense that if we lower δ(G), we cannot obtain the full range of values for k.
Keywords: claw-free, forbidden subgraphs, 2-factors, cycles.
2000 Mathematics Subject Classification: 05C38.
References
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Received 19 February 1999
Revised 24 January 2000
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