Let Ο l (G), Ο l (G), Ο l (G), and (G) denote, respectively, the list chromatic number, the list chromatic index, the list total chromatic number, and the maximum degree of a non-trivial connected outerplane graph G. We prove the following results. ( 1 and only if G is an odd cycle. This proves the
Matrix Choosability
β Scribed by Matt DeVos
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 149 KB
- Volume
- 90
- Category
- Article
- ISSN
- 0097-3165
No coin nor oath required. For personal study only.
β¦ Synopsis
Let F be a finite field with p c elements, let A be a n_n matrix over F, and let k be a positive integer. When is it true that for all X 1 , ...,
Ax= y? It is trivial that A has this property for k= p c &1 if det(A){0. The permanent lemma of Noga Alon proves that if perm(A){0, then A has this property for k=1. We will present a theorem which generalizes both of these facts, and then we will apply our theorem to prove ``choosability'' generalizations of Jaeger's 4-flow and 8-flow theorems in Z k p .
π SIMILAR VOLUMES
## Abstract We study circular choosability, a notion recently introduced by Mohar and Zhu. First, we provide a negative answer to a question of Zhu about circular cliques. We next prove that cch(__G__)=__O__(ch(__G__)+ln|__V__(__G__)|) for every graph __G__. We investigate a generalization of circu
Let S(r ) denote a circle of circumference r. The circular consecutive choosability ch cc (G) of a graph G is the least real number t such that
A graph G = (V, E ) with vertex set V and edge set E is called (a, b)-choosable ( a 2 2b) if for any collection {L(w)lv E V} of sets L ( v ) of cardinality a there exists a collection Giving a partial solution to a problem raised by Erdos, Rubin, and Taylor in 1979, we prove that every (2. 1)-choos
## Abstract Suppose the edges of a graph __G__ are assigned 3βelement lists of real weights. Is it possible to choose a weight for each edge from its list so that the sums of weights around adjacent vertices were different? We prove that the answer is positive for several classes of graphs, includi
This paper discusses the circular version of list coloring of graphs. We give two definitions of the circular list chromatic number (or circular choosability) c;l Γ°GΓ of a graph G and prove that they are equivalent. Then we prove that for any graph G, c;l Γ°GΓ ! l Γ°GΓ Γ 1. Examples are given to show