Abstract
A k-coloring of a graph G=(V,E) is a mapping c:V→{1,2,…,k}. The coloring c is injective if, for every vertex v∈V, all the neighbors of v are assigned with distinct colors. The injective chromatic number χ i (G) of G is the smallest k such that G has an injective k-coloring. In this paper, we prove that every K 4-minor free graph G with maximum degree Δ≥1 has \(\chi_{i}(G)\le \lceil \frac{3}{2}\Delta\rceil\). Moreover, some related results and open problems are given.
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References
Bondy JA, Murty USR (1976) Graph theory with applications. Macmillan, London
Bu Y, Chen D, Raspaud A, Wang W (2009) Injective coloring of plane graphs. Discrete Appl Math 157:663–672
Chang GJ, Kuo D (1996) The L(2,1)-labelling problem on graphs. SIAM J Discrete Math 9:309–316
Doyon A, Hahn G, Raspaud A (2010) Some bounds on the injective chromatic number of graphs. Discrete Math 310:585–590
Duffin RJ (1965) Topology of series-parallel networks. J Math Anal Appl 10:303–318
Gonçalves D (2008) On the L(p,1)-labelling of graphs. Discrete Math 308:1405–1414
Griggs JR, Yeh RK (1992) Labelling graphs with a condition at distance 2. SIAM J Discrete Math 5:586–595
Hahn G, Kratochvíl J, Širáň J, Sotteau D (2002) On the injective chromatic number of graphs. Discrete Math 256:179–192
Havet F, Reed B, Sereni JS (2008) L(2,1)-labelling of graphs. In: Proceedings of the nineteenth annual ACM-SIAM symposium on discrete algorithms. ACM, New York, pp 621–630
Kim SJ, Oum S (2009) Injective chromatic number and chromatic number of the square of graphs. Preprint
Král D, Škrekovski R (2003) A theorem about the channel assignment problem. SIAM J Discrete Math 16:426–437
Lih KW, Wang W, Zhu X (2003) Coloring the square of a K 4-minor free graph. Discrete Math 269:303–309
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Research supported partially by NSFC (No.11071223) and ZJNSF (No.Z6090150).
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Chen, M., Hahn, G., Raspaud, A. et al. Some results on the injective chromatic number of graphs. J Comb Optim 24, 299–318 (2012). https://doi.org/10.1007/s10878-011-9386-2
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DOI: https://doi.org/10.1007/s10878-011-9386-2