Coloring the Cartesian sum of graphs
نویسندگان
چکیده
منابع مشابه
Coloring the Cartesian sum of graphs
For graphs G and H, let G ⊕ H denote their Cartesian sum. We investigate the chromatic number and the circular chromatic number for G ⊕ H. It is proved that for any graphs G and H, χ(G ⊕ H) ≤ max{dχc(G)χ(H)e, dχ(G)χc(H)e}. It is conjectured that for any graphs G and H, χc(G ⊕H) ≤ max{χ(H)χc(G), χ(G)χc(H)}. We confirm this conjecture for graphs G and H with special values of χc(G) and χc(H). The...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2008
ISSN: 0012-365X
DOI: 10.1016/j.disc.2007.11.005