The chromatic index of graphs with large maximum degree
نویسندگان
چکیده
منابع مشابه
The chromatic index of graphs with large maximum degree
By Vizing’s theorem, the chromatic index x’(G) of a simple graph G satisfies d(G) Li 1 V(G)1 J + ir, where r is the number of vertices of maximum degree. A graph G is critical if G is Class 2 and x’(H) < x’(G) for all prop...
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Let G be a color-critical graph with χ(G) ≥ Δ(G) = 2t + 1 ≥ 5 such that the subgraph of G induced by the vertices of degree 2t+1 has clique number at most t−1. We prove that then either t ≥ 3 and G = K2t+2 or t = 2 and G ∈ {K6, O5}, where O5 is a special graph with χ(O5) = 5 and |O5| = 9. This result for t ≥ 3 improves a case of a theorem by Rabern [9] and for t = 2 answers a question raised by...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1983
ISSN: 0012-365X
DOI: 10.1016/0012-365x(83)90074-2