Discussiones Mathematicae Graph Theory 27(2) (2007) 323-332
doi: 10.7151/dmgt.1364

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VERTEX-DOMINATING CYCLES IN 2-CONNECTED BIPARTITE GRAPHS

Tomoki Yamashita

Department of Mathematics
School of Dentistry, Asahi University
1851 Hozumi, Gifu 501-0296, Japan
e-mail: tomoki@dent.asahi-u.ac.jp

Abstract

A cycle C is a vertex-dominating cycle if every vertex is adjacent to some vertex of C. Bondy and Fan [4] showed that if G is a 2-connected graph with δ(G) ≥ [1/3](|V(G)| −4), then G has a vertex-dominating cycle. In this paper, we prove that if G is a 2-connected bipartite graph with partite sets V1 and V2 such that δ(G) ≥ [1/3]( max{|V1|, |V2|}+1), then G has a vertex-dominating cycle.

Keywords: vertex-dominating cycle, dominating cycle, bipartite graph.

2000 Mathematics Subject Classification: 05C38, 05C45.

References

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Received 28 April 2006
Revised 23 February 2007
Accepted 23 February 2007