List Supermodular Coloring with Shorter Lists
نویسندگان
چکیده
منابع مشابه
Between coloring and list-coloring: μ-coloring
A new variation of the coloring problem, μ-coloring, is defined in this paper. Given a graph G and a function μ, a μ-coloring is a coloring where each vertex v of G must receive a color at most μ(v). It is proved that μ-coloring lies between coloring and list-coloring, in the sense of generalization of problems and computational complexity. The notion of perfection is extended for μ-coloring, l...
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Let G be a graph embedded on a surface Sε with Euler genus ε > 0, and let P ⊂ V (G) be a set of vertices mutually at distance at least 4 apart. Suppose all vertices of G have H(ε)-lists and the vertices of P are precolored, where H(ε) = ⌊ 7+ √ 24ε+1 2 ⌋ is the Heawood number. We show that the coloring of P extends to a list-coloring of G and that the distance bound of 4 is best possible. Our re...
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The dichromatic number ~ χ(D) of a digraph D is the least number k such that the vertex set of D can be partitioned into k parts each of which induces an acyclic subdigraph. Introduced by Neumann-Lara in 1982, this digraph invariant shares many properties with the usual chromatic number of graphs and can be seen as the natural analog of the graph chromatic number. In this paper, we study the li...
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ژورنال
عنوان ژورنال: Combinatorica
سال: 2018
ISSN: 0209-9683,1439-6912
DOI: 10.1007/s00493-018-3830-1