20 search results - page 3 / 4 » Circular Chromatic Number of Hypergraphs |
JCT
2010
13 years 4 months ago
2010
We prove that for every k and every ε > 0, there exists g such that every graph with tree-width at most k and odd-girth at least g has circular chromatic number at most 2 + ε...
DM
2008
13 years 5 months ago
2008
For graphs G and H, let G H denote their Cartesian sum. This paper investigates the chromatic number and the circular chromatic number for GH. It is proved that (G H) max{ c(G)...
JCT
2007
13 years 5 months ago
2007
We show that for each ε > 0 and each integer ∆ ≥ 1, there exists a number g such that for any graph G of maximum degree ∆ and girth at least g, the circular chromatic in...
COMBINATORICS
2000
13 years 5 months ago
2000
A mixed hypergraph is a triple H = (V, C, D) where V is the vertex set and C and D are families of subsets of V , the C-edges and D-edges, respectively. A k-colouring of H is a ma...
ENDM
2007
13 years 5 months ago
2007
The circular chromatic number of a graph is a well-studied refinement of the chromatic number. Circular-perfect graphs is a superclass of perfect graphs defined by means of this...