In this paper, we shall consider the following problem: up to duality, is a connected matroid reconstructible from its connectivity function? Cunningham conjectured that this question has an affirmative answer, but Seymour gave a counter-example for it. In the same paper, Seymour proved that a conne
Weight distribution of the bases of a binary matroid
โ Scribed by S. Zhou
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 399 KB
- Volume
- 11
- Category
- Article
- ISSN
- 0893-9659
No coin nor oath required. For personal study only.
โฆ Synopsis
Let M be a weighted binary matroid and UJ~ < . < w,,, be the increasing sequence of all possible distinct weights of bases of M. We give a sufficient condition for the property that Wl,..., wm is an arithmetical progression of common difference d. We also give conditions which guarantee that wi+l -wi 5 d, 1 5 i 5 m -1. Dual forms for these results are given also.
๐ SIMILAR VOLUMES
We study the lattice (grid) generated by the incidence vectors of cocycles of a binary matroid and its dual tattice. We characterize those binary matroids for which the obvious necessary conditions for a vector to belong to the cocycle lattice are also sufficient. This characterization yields a poly
1+ Introductim ## 2. &tnatrsids An Z-nt~rfpis is 8 @-I matrix having thk. I+ 7 .Fyaty tha? some permuta-tion of its distinct ~ofutnns is the matrix J: I,\* fair some intttgcr r 2 '1. JP is the r \* r matrix of all 1's and lr is thbz F X r identity. Given an [-maitrix with r rows. the follc:wing pr