In this paper Gallai’s inequality on the number of edges in critical graphs is generalized for reducible additive induced-hereditary properties of graphs in the following way. Let (k ≥ 2) be additive induced-hereditary properties, and . Suppose that G is an -critical graph with n vertices and m edges. Then 2m ≥ δn + (δ-2)/(δ²+2δ-2)*n + (2δ)/(δ²+2δ-2) unless = ² or . The generalization of Gallai’s inequality for -choice critical graphs is also presented.
@article{bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1141, author = {Peter Mih\'ok and Riste Skrekovski}, title = {Gallai's innequality for critical graphs of reducible hereditary properties}, journal = {Discussiones Mathematicae Graph Theory}, volume = {21}, year = {2001}, pages = {167-177}, zbl = {1002.05025}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1141} }
Peter Mihók; Riste Skrekovski. Gallai's innequality for critical graphs of reducible hereditary properties. Discussiones Mathematicae Graph Theory, Tome 21 (2001) pp. 167-177. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1141/
[000] [1] G.A. Dirac, A theorem of R.L. Brooks and a conjecture of H. Hadwiger, Proc. London Math. Soc. 7 (1957) 161-195, doi: 10.1112/plms/s3-7.1.161. | Zbl 0077.17002
[001] [2] O.V. Borodin, A.V. Kostochka and B. Toft, Variable degeneracy: extensions of Brooks' and Gallai's theorems, Discrete Math. 214 (2000) 101-112, doi: 10.1016/S0012-365X(99)00221-6. | Zbl 0949.05029
[002] [3] M. Borowiecki, E. Drgas-Burchardt and P. Mihók, Generalized list colourings of graphs, Discuss. Math. Graph Theory 15 (1995) 185-193, doi: 10.7151/dmgt.1016. | Zbl 0845.05046
[003] [4] M. Borowiecki and P. Mihók, Hereditary properties of graphs, in: V.R. Kulli, ed., Advances in Graph Theory (Vishwa International Publication, Gulbarga, 1991) 41-68.
[004] [5] P. Erdős, A.L. Rubin and H. Taylor, Choosability in graphs, in: Proc. West Coast Conf. on Combin., Graph Theory and Computing, Congressus Numerantium XXVI (1979) 125-157.
[005] [6] T. Gallai, Kritische Graphen I, Publ. Math. Inst. Hung. Acad. Sci. 8 (1963) 373-395. | Zbl 0144.23204
[006] [7] T.R. Jensen and B. Toft, Graph Coloring Problems (Wiley, New York, 1995).
[007] [8] A.V. Kostochka, M. Stiebitz and B. Wirth, The colour theorems of Brooks and Gallai extended, Discrete Math. 162 (1996) 299-303, doi: 10.1016/0012-365X(95)00294-7. | Zbl 0871.05024
[008] [9] A.V. Kostochka and M. Stiebitz, On the number of edges in colour-critical graphs and hypergraphs, Combinatorica 20 (2000) 521-530, doi: 10.1007/s004930070005. | Zbl 0996.05046
[009] [10] A.V. Kostochka and M. Stiebitz, A New Lower Bound on the Number of Edges in Colour-Critical Graphs and Hypergraphs, manuscript, 1999. | Zbl 1020.05028
[010] [11] M. Krivelevich, On the minimal number of edges in color-critical graphs, Combinatorica 17 (1997) 401-426, doi: 10.1007/BF01215921. | Zbl 0902.05025
[011] [12] M. Krivelevich, An improved bound on the minimal number of edges in color-critical graphs, Electronic J. Combin. 5 (1998) #R4. | Zbl 0885.05063
[012] [13] P. Mihók, On the structure of the point arboricity critical graphs, Math. Slovaca 31 (1981) 101-108. | Zbl 0463.05042
[013] [14] R. Skrekovski, On the critical point-arboricity graphs, manuscript, 1998.
[014] [15] C. Thomassen, Color-critical graphs on a fixed surface, J. Combin. Theory (B) 70 (1997) 67-100, doi: 10.1006/jctb.1996.1722. | Zbl 0883.05051
[015] [16] V.G. Vizing, Coloring the vertices of a graph in prescribed colours (in Russian), Diskret. Analiz 29 (1976) 3-10.