Partial k-trees with maximum chromatic number
نویسندگان
چکیده
منابع مشابه
Distance graphs with maximum chromatic number
Let D be a finite set of integers. The distance graph G(D) has the set of integers as vertices and two vertices at distance d ∈ D are adjacent in G(D). A conjecture of Xuding Zhu states that if the chromatic number of G(D) achieves its maximum value |D| + 1 then the graph has a clique of order |D|. We prove that the chromatic number of a distance graph with D = {a, b, c, d} is five if and only ...
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Let c be a proper k-coloring of a connected graph G. Let Π = {S1, S2, . . . , Sk} be the induced partition of V (G) by c, where Si is the partition class having all vertices with color i. The color code cΠ(v) of vertex v is the ordered k-tuple (d(v, S1), d(v, S2), . . . , d(v, Sk)), where d(v, Si) = min{d(v, x)|x ∈ Si}, for 1 ≤ i ≤ k. If all vertices of G have distinct color codes, then c is ca...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2002
ISSN: 0012-365X
DOI: 10.1016/s0012-365x(02)00586-1