Title
An Obstacle to a Decomposition Theorem for Near-Regular Matroids
Abstract
Seymour's decomposition theorem [J. Combin. Theory Ser. B, 28 (1980), pp. 305-359] for regular matroids states that any matroid representable over both $\mathrm{GF}(2)$ and $\mathrm{GF}(3)$ can be obtained from matroids that are graphic, cographic, or isomorphic to $R_{10}$ by 1-, 2-, and 3-sums. It is hoped that similar characterizations hold for other classes of matroids, notably for the class of near-regular matroids. Suppose that all near-regular matroids can be obtained from matroids that belong to a few basic classes through $k$-sums. Also suppose that these basic classes are such that, whenever a class contains all graphic matroids, it does not contain all cographic matroids. We show that, in that case, 3-sums will not suffice.
Year
DOI
Venue
2011
10.1137/090759616
SIAM Journal on Discrete Mathematics
Keywords
Field
DocType
theory ser,graphic matroids,cographic matroids,basic class,near-regular matroids,regular matroids state,j. combin,similar characterization,decomposition theorem,matroid representable
Matroid,Graphics,Discrete mathematics,Obstacle,Combinatorics,Decomposition method (constraint satisfaction),Isomorphism,Decomposition theorem,Graphic matroid,Mathematics
Journal
Volume
Issue
ISSN
25
1
0895-4801
Citations 
PageRank 
References 
2
0.65
10
Authors
3
Name
Order
Citations
PageRank
Dillon Mayhew110218.63
Geoff Whittle247157.57
Stefan H. M. van Zwam3608.60