A copy of this work was available on the public web and has been preserved in the Wayback Machine. The capture dates from 2019; you can also visit the original URL.
The file type is application/pdf
.
Filters
Branch-Width and Well-Quasi-Ordering in Matroids and Graphs
2002
Journal of combinatorial theory. Series B (Print)
We prove that a class of matroids representable over a fixed finite field and with bounded branch-width is well-quasi-ordered under taking minors. ...
With some extra work, the result implies Robertson and Seymour's result that graphs with bounded tree-width (or equivalently, bounded branch-width) are well-quasi-ordered under taking minors. ...
For example, the relation ''A is isomorphic to a minor of B'' is a quasi-order on any set of graphs or BRANCH-WIDTH AND WELL-QUASI-ORDERING matroids. ...
doi:10.1006/jctb.2001.2082
fatcat:owsrw6mjpngavhief37dum5mmy
Well-quasi-ordering in lattice path matroids
[article]
2018
arXiv
pre-print
Though lattice path matroids are not well-quasi-ordered, we prove that lattice path matroids of bounded branch-width are well-quasi-ordered. ...
Lattice path matroids form a subclass of transversal matroids and were introduced by Bonin, de Mier and Noy. Transversal matroids are not well-quasi-ordered, even when the branch-width is restricted. ...
In essence, a graph class or matroid class is well-quasi-ordered if and only if it does not have a bad sequence, as graph and matroid classes do not contain infinite decreasing sequences. ...
arXiv:1806.10260v1
fatcat:37vdwy3qqja6pdr4umhlk42gue
TOWARDS A MATROID-MINOR STRUCTURE THEORY
[chapter]
2007
Combinatorics, Complexity, and Chance
For example, Robertson and Seymour [21] prove that any class of graphs of bounded tree width is well-quasi-ordered so that G is well-quasi-ordered. ...
Branch width is equivalent to tree width in that a class of graphs, or matroids, has bounded branch width if and only if it has bounded tree width. ...
doi:10.1093/acprof:oso/9780198571278.003.0005
fatcat:rnrqxwsn6fdhdixknsck3bxqqy
Special issue in honor of Geoff Whittle
2013
Advances in Applied Mathematics
This collaboration has produced matroid analogues of the well-quasi-ordering results from Robertson and Seymour's monumental Graph Minors Project. ...
Tutte and Paul Seymour as the most significant ever done in matroid theory. In this preface, we will introduce matroids after giving some biographical details of Geoff's life. ...
In 2009, Jim, Bert, and Geoff announced that they had proved that the class of binary matroids is well-quasi-ordered. ...
doi:10.1016/j.aam.2012.08.006
fatcat:54tqw7x7onf7jgqfl6f4vkopne
Branch-depth: Generalizing tree-depth of graphs
[article]
2019
arXiv
pre-print
Furthermore we investigate various potential generalizations of tree-depth to matroids and prove that matroids representable over a fixed finite field having no large circuits are well-quasi-ordered by ...
For a graph G = (V,E) and a subset A of E we let λ_G (A) be the number of vertices incident with an edge in A and an edge in E ∖ A. ...
circuits are well-quasi-ordered by the matroid restriction. ...
arXiv:1903.11988v1
fatcat:gi4wqco2effijji7oqduxlh2qq
Rank-width and well-quasi-ordering of skew-symmetric or symmetric matrices
2012
Linear Algebra and its Applications
This generalizes three theorems on well-quasi-ordering of graphs or matroids admitting good tree-like decompositions; (1) Robertson and Seymour's theorem for graphs of bounded tree-width, (2) Geelen, Gerards ...
, and Whittle's theorem for matroids representable over a fixed finite field having bounded branch-width, and (3) Oum's theorem for graphs of bounded rank-width with respect to pivot-minors. ...
[8] on wellquasi-ordering of F-representable matroids of bounded branch-width for a finite field F as well as the theorem by Robertson and Seymour [14] on well-quasi-ordering of graphs of bounded ...
doi:10.1016/j.laa.2011.09.027
fatcat:ocgmcqgwr5fofgqhliewxizody
Branch and Tree Decomposition Techniques for Discrete Optimization
[chapter]
2005
Emerging Theory, Methods, and Applications
in monadic second order logic. ...
The algorithmic importance of branch decompositions and tree decompositions for solving NP-hard problems modelled on graphs was first realized by computer scientists in relation to formulating graph problems ...
the Netherlands Organization for Scientific Research (project Treewidth and Combinatorial Optimization). ...
doi:10.1287/educ.1053.0017
fatcat:czyk6fbzdre53cp4zxfyckd5ga
Well-quasi-ordering of matrices under Schur complement and applications to directed graphs
2012
European journal of combinatorics (Print)
In [Rank-Width and Well-Quasi-Ordering of Skew-Symmetric or Symmetric Matrices, arXiv:1007.3807v1] Oum proved that, for a fixed finite field F, any infinite sequence M_1,M_2,... of (skew) symmetric matrices ...
We generalise this result to σ-symmetric matrices introduced by Rao and myself in [The Rank-Width of Edge-Coloured Graphs, arXiv:0709.1433v4]. ...
Courcelle and the anonymous referee for their helpful comments. The author is supported by the DORSO project of ''Agence Nationale Pour la Recherche''. ...
doi:10.1016/j.ejc.2012.03.034
fatcat:g3ivd3hytrcxjjwgsakwf3rzpq
Rank-width: Algorithmic and structural results
2017
Discrete Applied Mathematics
This survey aims to summarize known algorithmic and structural results on rank-width of graphs. ...
Rank-width is a width parameter of graphs describing whether it is possible to decompose a graph into a tree-like structure by 'simple' cuts. ...
Kanté, Eun Jung Kim, O-joung Kwon, and Jisu Jeong for their helpful comments on an early draft of this paper. ...
doi:10.1016/j.dam.2016.08.006
fatcat:pvvs5yq5hvhxderfshfih3atti
Rank-Width and Well-Quasi-Ordering
2008
SIAM Journal on Discrete Mathematics
By extending their arguments, Geelen, Gerards, and Whittle (2002) proved that binary matroids of bounded branch-width are well-quasi-ordered by the matroid minor relation. ...
We prove that graphs of bounded rank-width are well-quasi-ordered by the vertexminor relation; in other words, for every infinite sequence G 1 , G 2 , . . . of graphs of rank-width (or clique-width) at ...
This work was performed while the author was at the Program in Applied and Computational Mathematics, Princeton University, Princeton, New Jersey and partially supported by the SRC program of Korea Science ...
doi:10.1137/050629616
fatcat:dfypq474zbatxoph7im6pfe3ty
Some Hard Problems on Matroid Spikes
2007
Theory of Computing Systems
Whittle, Branch-Width and Well-Quasi-
Ordering in Matroids and Graphs, J. Combin. Theory Ser. B 84 (2002), 270–290.
5. P. ...
On the other hand, an interesting class
of matroids of branch-width three, called spikes, is not well-quasi-ordered over
any infinite field. ...
doi:10.1007/s00224-007-1307-5
fatcat:m2m4ooibbne2leibtycu5xd34y
Trees, grids, and MSO decidability: From graphs to matroids
2006
Theoretical Computer Science
Whittle, Branchwidth and well-quasi-ordering in matroids and graphs, J. Combin. Theory Ser. B 84 (2002) 270-290; J.F. Geelen, A.H.M. Gerards, N. Robertson, G.P. ...
(Matroids can be viewed as a wide generalization of graphs, and they seem to capture some second order properties in a more suitable way than graphs themselves, cf. the recent development in matroid structure ...
Courcelle, the organizer of the workshop on "Logic and Graph Transformations" at the ICGT 2004 conference, for inviting us to present our research results there. ...
doi:10.1016/j.tcs.2005.10.006
fatcat:dtsh4w7hs5dbtkz6nyqjef3cp4
Graph minor theory
2005
Bulletin of the American Mathematical Society
We describe the precise formulation of the main results and survey some of its applications to algorithmic and structural problems in graph theory. ...
in a tree-like fashion from graphs that can almost be embedded in a fixed surface. ...
So Wagner's conjecture follows in this case if we show that for any positive integer k, the class of graphs with tree-width at most k is well-quasi-ordered by the minor relation. ...
doi:10.1090/s0273-0979-05-01088-8
fatcat:nwz23353z5bubdsyobrdls3ksu
On the Excluded Minors for Matroids of Branch-Width Three
2002
Electronic Journal of Combinatorics
We also construct numbers of such ternary and quaternary matroids $ M$, and provide a simple practical algorithm for finding a width-$3$ branch-decomposition of a matroid. ...
Whittle, On Matroids of Branch-Width Three, submitted 2001] that if $M$ is an excluded minor for matroids of branch-width $3$, then $ M$ has at most $14$ elements. ...
Besides others, we want to mention the following recent works: well-quasi-ordering of matroids of bounded branch-width over finite fields [4] , sizebounds on the excluded minors for matroids of fixed ...
doi:10.37236/1648
fatcat:rzviyjy7cff2hnjnnzkutlkoti
Obstructions for bounded branch-depth in matroids
[article]
2020
arXiv
pre-print
We prove that matroids with sufficiently large branch-depth either contain the cycle matroid of a large fan graph as a minor or have large branch-width. ...
DeVos, Kwon, and Oum introduced the concept of branch-depth of matroids as a natural analogue of tree-depth of graphs. ...
If G has branch-width at most w, then the quasi-graphic matroid M :" M pG, B, L, Fq has branch-width at most w`2.
Theorem 5. 4 ( 4 Robertson and Seymour [18, (2.1)] and [19, (5.1)]). ...
arXiv:2003.13975v1
fatcat:3ob47hcvtzaq5ccgg7opzfjgje
« Previous
Showing results 1 — 15 out of 142 results