Abstract
A graph G is coordinated if the minimum number of colors that can be assigned to the cliques of H in such a way that no two cliques with non-empty intersection receive the same color is equal to the maximum number of cliques of H with a common vertex, for every induced subgraph H of G. Coordinated graphs are a subclass of perfect graphs. The list of minimal forbidden induced subgraphs for the class of coordinated graphs is not known. In this paper, we present a partial result in this direction, that is, we characterize coordinated graphs by minimal forbidden induced subgraphs when the graph is either a line graph, or the complement of a forest.
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Bonomo F, Chudnovsky M, Durán G (2008) Partial characterizations of clique-perfect graphs I: sublcasses of claw-free graphs. Discrete Appl Math 156: 1058–1082
Bonomo F, Durán G, Groshaus M (2007) Coordinated graphs and clique graphs of clique-Helly perfect graphs. Util Math 72: 175–191
Chudnovsky M, Cornuéjols G, Liu X, Seymour P, Vušković K (2005) Recognizing berge graphs. Combinatorica 25(2): 143–186
Chudnovsky M, Robertson N, Seymour P, Thomas R (2006) The strong perfect graph theorem. Ann Math 164: 51–229
de Werra D (1978) On line perfect graphs. Math Program 15: 236–238
Golumbic M (2004) Algorithmic graph theory and perfect graphs, 2nd edn. Annals of Discrete Mathematics, vol 57. North-Holland, Amsterdam
Guruswami V, Pandu Rangan C (2000) Algorithmic aspects of clique-transversal and clique-independent sets. Discrete Appl Math 100(3): 183–202
Kőnig D (1916) Über Graphen und ihre Anwendung auf Determinantentheorie und Mengenlehre. Math Ann 77: 453–465
Kőnig D (1931) Graphok és Matrixok. Matematikai és Fizikai Lapok 38: 116–119
Lehot P (1974) An optimal algorithm to detect a line graph and output its root graph. J ACM 21(4): 569–575
Maffray F (1992) Kernels in perfect line-graphs. J Comb Theory Ser B 55: 1–8
Prisner E (1993) Hereditary clique-Helly graphs. J Comb Math Comb Comput 14: 216–220
Soulignac F, Sueiro G (2006) Exponential families of minimally non-coordinated graphs (submitted)
Soulignac F, Sueiro G (2006) NP-hardness of the recognition of coordinated graphs. Ann Oper Res (in press). doi:10.1007/s10479-008-0392-4
Trotter L (1977) Line perfect graphs. Math Program 12: 255–259
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F. Bonomo, F. Soulignac, and G. Sueiro’s research partially supported by UBACyT Grant X184 (Argentina), and CNPq under PROSUL project Proc. 490333/2004-4 (Brazil).
The research of G. Durán is partially supported by FONDECyT Grant 1080286 and Millennium Science Institute “Complex Engineering Systems” (Chile), and CNPq under PROSUL project Proc. 490333/2004-4 (Brazil).
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Bonomo, F., Durán, G., Soulignac, F. et al. Partial characterizations of coordinated graphs: line graphs and complements of forests. Math Meth Oper Res 69, 251–270 (2009). https://doi.org/10.1007/s00186-008-0257-2
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DOI: https://doi.org/10.1007/s00186-008-0257-2