Domination in partitioned graphs
Discussiones Mathematicae. Graph Theory, Tome 22 (2002) no. 1, pp. 199-210
Cet article a éte moissonné depuis la source Library of Science
Let V₁, V₂ be a partition of the vertex set in a graph G, and let γ_i denote the least number of vertices needed in G to dominate V_i. We prove that γ₁+γ₂ ≤ [4/5]|V(G)| for any graph without isolated vertices or edges, and that equality occurs precisely if G consists of disjoint 5-paths and edges between their centers. We also give upper and lower bounds on γ₁+γ₂ for graphs with minimum valency δ, and conjecture that γ₁+γ₂ ≤ [4/(δ+3)]|V(G)| for δ ≤ 5. As δ gets large, however, the largest possible value of (γ₁+γ₂)/|V(G)| is shown to grow with the order of (logδ)/(δ).
Keywords:
graph, dominating set, domination number, vertex partition
@article{DMGT_2002_22_1_a16,
author = {Tuza, Zsolt and Vestergaard, Preben},
title = {Domination in partitioned graphs},
journal = {Discussiones Mathematicae. Graph Theory},
pages = {199--210},
year = {2002},
volume = {22},
number = {1},
language = {en},
url = {http://geodesic.mathdoc.fr/item/DMGT_2002_22_1_a16/}
}
Tuza, Zsolt; Vestergaard, Preben. Domination in partitioned graphs. Discussiones Mathematicae. Graph Theory, Tome 22 (2002) no. 1, pp. 199-210. http://geodesic.mathdoc.fr/item/DMGT_2002_22_1_a16/
[1] B.L. Hartnell and P.D. Vestergaard, Partitions and dominations in a graph, Manuscript, pp. 1-10.
[2] T.W. Haynes, S.T. Hedetniemi and P.J. Slater, Fundamentals of domination in graphs (Marcel Dekker, Inc., New York, N.Y., 1998).
[3] C. Payan and N.H. Xuong, Domination-balanced graphs, J. Graph Theory 6 (1982) 23-32, doi: 10.1002/jgt.3190060104.
[4] B. Reed, Paths, stars and the number three, Combin. Probab. Comput. 5 (3) (1996) 277-295, doi: 10.1017/S0963548300002042.
[5] S.M. Seager, Partition dominations of graphs of minimum degree 2, Congressus Numerantium 132 (1998) 85-91.