𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Circular chromatic number and Mycielski construction

✍ Scribed by Hossein Hajiabolhassan; Xuding Zhu


Publisher
John Wiley and Sons
Year
2003
Tongue
English
Weight
94 KB
Volume
44
Category
Article
ISSN
0364-9024

No coin nor oath required. For personal study only.

✦ Synopsis


Abstract

This paper gives a sufficient condition for a graph G to have its circular chromatic number equal to its chromatic number. By using this result, we prove that for any integer t β‰₯ 1, there exists an integer n such that for all $k \ge n, \chi _c (M^t(K_k)),= \chi(M^t(K_k))$. Β© 2003 Wiley Periodicals, Inc. J Graph Theory 44: 106–115, 2003


πŸ“œ SIMILAR VOLUMES


The fractional chromatic number of mycie
✍ Michael Larsen; James Propp; Daniel Ullman πŸ“‚ Article πŸ“… 1995 πŸ› John Wiley and Sons 🌐 English βš– 236 KB

The most familiar construction of graphs whose clique number is much smaller than their chromatic number is due to Mycielski, who constructed a sequence G, of triangle-free graphs with ,y(G,) = n. In this article, w e calculate the fractional chromatic number of G, and show that this sequence of num

Circular Chromatic Numbers and Fractiona
✍ G.J. Chang; L. Huang; X. Zhu πŸ“‚ Article πŸ“… 1998 πŸ› Elsevier Science 🌐 English βš– 171 KB

This paper studies circular chromatic numbers and fractional chromatic numbers of distance graphs G(Z , D) for various distance sets D. In particular, we determine these numbers for those D sets of size two, for some special D sets of size three, for

Circular chromatic number of subgraphs
✍ Hossein Hajiabolhassan; Xuding Zhu πŸ“‚ Article πŸ“… 2003 πŸ› John Wiley and Sons 🌐 English βš– 107 KB

## Abstract This paper proves that every (__n__ + )‐chromatic graph contains a subgraph __H__ with $\chi \_c (H) = n$. This provides an easy method for constructing sparse graphs __G__ with $\chi\_c (G) = \chi ( G) = n$. It is also proved that for any Ρ > 0, for any fraction __k/d__ > 2, there exis

Fractional chromatic number and circular
✍ Daphne Der-Fen Liu; Xuding Zhu πŸ“‚ Article πŸ“… 2004 πŸ› John Wiley and Sons 🌐 English βš– 136 KB

## Abstract An Erratum has been published for this article in Journal of Graph Theory 48: 329–330, 2005. Let __M__ be a set of positive integers. The distance graph generated by __M__, denoted by __G__(__Z, M__), has the set __Z__ of all integers as the vertex set, and edges __ij__ whenever |__i__

On the circular chromatic number of circ
✍ Arnaud PΓͺcher; Xuding Zhu πŸ“‚ Article πŸ“… 2006 πŸ› John Wiley and Sons 🌐 English βš– 168 KB

## Abstract This article studies the circular chromatic number of a class of circular partitionable graphs. We prove that an infinite family of circular partitionable graphs __G__ has $\chi\_ c (G) = \chi(G)$. A consequence of this result is that we obtain an infinite family of graphs __G__ with th

The circular chromatic number of a digra
✍ Drago Bokal; GasΜ†per Fijavz; Martin Juvan; P. Mark Kayll; Bojan Mohar πŸ“‚ Article πŸ“… 2004 πŸ› John Wiley and Sons 🌐 English βš– 127 KB πŸ‘ 1 views

## Abstract We introduce the circular chromatic number Ο‡~__c__~ of a digraph and establish various basic results. They show that the coloring theory for digraphs is similar to the coloring theory for undirected graphs when independent sets of vertices are replaced by acyclic sets. Since the directe