On improper interval edge colourings
نویسندگان
چکیده
منابع مشابه
On monochromatic component size for improper colourings
This paper concerns improper λ-colourings of graphs and focuses on the sizes of the monochromatic components (i.e., components of the subgraphs induced by the colour classes). Consider the following three simple operations, which should, heuristically, help reduce monochromatic component size: (a) assign to a vertex the colour that is least popular among its neighbours; (b) change the colours o...
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We prove that if H = (V (H), E(H)) is a hypergraph, γ is an edge colouring of H, and S ⊆ V (H) such that any permutation of S is an automorphism of H, then there exists a permutation π of E(H) such that |π(E)| = |E| and π(E)\S = E \S for each E ∈ E(H), and such that the edge colouring γ′ of H given by γ′(E) = γ(π−1(E)) for each E ∈ E(H) is almost regular on S. The proof is short and elementary....
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ژورنال
عنوان ژورنال: Czechoslovak Mathematical Journal
سال: 2016
ISSN: 0011-4642,1572-9141
DOI: 10.1007/s10587-016-0313-7