8 search results - page 1 / 2 » Excluding a planar graph from GF(q)-representable matroids |
JCT
2007
13 years 4 months ago
2007
Abstract. We prove that a binary matroid with huge branchwidth contains the cycle matroid of a large grid as a minor. This implies that an infinite antichain of binary matroids ca...
GD
2006
Springer
13 years 8 months ago
2006
Springer
Tree decompositions of graphs are of fundamental importance in structural and algorithmic graph theory. Planar decompositions generalise tree decompositions by allowing an arbitrar...
MST
2011
12 years 7 months ago
2011
We study the complexity of testing if two given matroids are isomorphic. The problem is easily seen to be in Σ p 2. In the case of linear matroids, which are represented over pol...
CORR
2007
Springer
13 years 4 months ago
2007
Springer
We relate the notion of matroid pathwidth to the minimum trellis state-complexity (which we term trellis-width) of a linear code, and to the pathwidth of a graph. By reducing from ...
STOC
1990
ACM
13 years 8 months ago
1990
ACM
ions (Extended Abstract) Noga Alon Paul Seymour Robin Thomas Let G be an n-vertex graph with nonnegative weights whose sum is 1 assigned to its vertices, and with no minor isomorp...