Compatible systems of representatives
β Scribed by Martin Kochol
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 691 KB
- Volume
- 132
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
β¦ Synopsis
The main result of this paper can be quickly described as follows. Let G be a bipartite graph and assume that for any vertex v of G a strongly base orderable matroid is given on the set of edges adjacent with v. Call a subgraph of G a system of representatives of G if the edge neighborhood of each vertex of this subgraph is independent in the corresponding matroid. Two systems of representatives we call compatible if they have no common edge. We give a necessary and sufficient condition for G to have k pairwise compatible systems of representatives with at least d edges. Unfortunately, this condition is not sufficient if we deal with arbitrary matroids. Furthermore, we establish a listing variant of the Edmonds' covering theorem for strongly base orderable matroids.
π SIMILAR VOLUMES
Horiik, P., Extending partial systems of distinct representatives, Discrete Mathematics 91 (1991) 95-98. We determine a necessary and sufficient condition for a special class of families of sets to have the property that each partial SDR of cardinahty d can be extended to a total SDR. This result i
This paper applies a recent theorem about simultaneous systems of representatives for families of finite sets to obtain combinatorial results that are closely related to problems concerning minimal asymptotic bases in additive number theory.
## Abstract A natural digraph analog of the graph theoretic concept of βan independent setβ is that of βan acyclic set of vertices,β namely a set not spanning a directed cycle. By this token, an analog of the notion of coloring of a graph is that of decomposition of a digraph into acyclic sets. We