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Related papers: Splitters and Decomposers for Binary Matroids

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Seymour's decomposition theorem is a hallmark result in matroid theory presenting a structural characterization of the class of regular matroids. Formalization of matroid theory faces many challenges, most importantly that only a limited…

If $\mathcal{C}$ is a minor-closed class of matroids, the class $\mathcal{C}'$ of integer polymatroids whose natural matroids are in $\mathcal{C}$ is also minor closed, as is the class $\mathcal{C}'_k$ of $k$-polymatroids in $\mathcal{C}'$.…

Combinatorics · Mathematics 2024-08-07 Joseph E. Bonin , Kevin Long

In the matroid secretary problem we are given a stream of elements and asked to choose a set of elements that maximizes the total value of the set, subject to being an independent set of a matroid given in advance. The difficulty comes from…

Data Structures and Algorithms · Computer Science 2012-07-24 Michael Dinitz , Guy Kortsarz

Let $P(M)$ be the matroid base polytope of a matroid $M$. A {\em matroid base polytope decomposition} of $P(M)$ is a decomposition of the form $P(M) = \bigcup\limits_{i=1}^t P(M_{i})$ where each $P(M_i)$ is also a matroid base polytope for…

Combinatorics · Mathematics 2010-02-23 V. Chatelain , J. L. Ramirez Alfonsin

Fleischner introduced the idea of splitting a vertex of degree at least three in a connected graph and used the operation to characterize Eulerian graphs. Raghunathan et. al. extended the splitting operation from graphs to binary matroids.…

Combinatorics · Mathematics 2018-09-28 S. B. Dhotre , P. P. Malavadkar

We prove a splitter theorem for tight multimatroids, generalizing the corresponding result for matroids, obtained independently by Brylawski and Seymour. Further corollaries give splitter theorems for delta-matroids and ribbon graphs.

Combinatorics · Mathematics 2017-03-09 Carolyn Chun , Deborah Chun , Steven D. Noble

We give an excluded-minor characterization for the class of matroids M in which M\e or M/e is binary for all e in E(M). This class is closely related to the class of matroids in which every member is binary or can be obtained from a binary…

Combinatorics · Mathematics 2013-07-30 James Oxley , Jesse Taylor

Raghunathan at al. [9] introduced splitting operation with respect to a pair of element for binary matroid and characterized Eulerian binary matroids using it. In general, the splitting operation does not preserve the graphicness property…

Combinatorics · Mathematics 2020-02-13 Ganesh Mundhe , K. V. Dalvi

Let $M$ be a $3$-connected matroid. A pair $\{e,f\}$ in $M$ is detachable if $M \backslash e \backslash f$ or $M / e / f$ is $3$-connected. Williams (2015) proved that if $M$ has at least 13 elements, then at least one of the following…

Combinatorics · Mathematics 2025-09-15 Nick Brettell , Charles Semple , Gerry Toft

Let $M$ be an internally $4$-connected binary matroid with every element in three triangles. Then $M$ has at least four elements $e$ such that si$(M/e)$ is internally 4-connected.

Combinatorics · Mathematics 2016-08-23 Carolyn Chun , James Oxley

Motivated by Kontsevich's graph complexes, this paper gives a systematic study of matroid complexes. We construct deletion and contraction bicomplexes on the vector space spanned by matroid classes equipped with ground-set orientations,…

Combinatorics · Mathematics 2026-05-26 Juliette Bruce , Jacob Bucciarelli , Bailee Zacovic

The class of cographs or complement-reducible graphs is the class of graphs that can be generated from $K_1$ using the operations of disjoint union and complementation. By analogy, this paper introduces the class of binary comatroids as the…

Combinatorics · Mathematics 2021-10-20 James Oxley , Jagdeep Singh

Halin proved that every minimally $k$-connected graph has a vertex of degree $k$. More generally, does every minimally vertically $k$-connected matroid have a $k$-element cocircuit? Results of Murty and Wong give an affirmative answer when…

Combinatorics · Mathematics 2022-05-27 James Oxley , Zach Walsh

The class of 2-regular matroids is a natural generalisation of regular and near-regular matroids. We prove an excluded-minor characterisation for the class of 2-regular matroids. The class of 3-regular matroids coincides with the class of…

Combinatorics · Mathematics 2023-09-07 Nick Brettell , James Oxley , Charles Semple , Geoff Whittle

Let $M$ be a 3-connected binary matroid and let $Y(M)$ be the set of elements of $M$ avoiding at least $r(M)+1$ non-separating cocircuits of $M$. Lemos proved that $M$ is non-graphic if and only if $Y(M)\neq\emp$. We generalize this result…

Combinatorics · Mathematics 2012-11-27 João Paulo Costalonga

Adding elements to matroids can be fraught with difficulty. In the V\'amos matroid $V_8$, there are four independent sets $X_1,X_2, X_3,$ and $X_4$ such that $(X_1 \cup X_2,X_3 \cup X_4)$ is a $3$-separation while exactly three of the local…

Combinatorics · Mathematics 2018-05-15 James Oxley

A matroid $N$ is a lift of a binary matroid $M$, if $N=Q\backslash X$ when $Q/X=M$ for some binary matroid $Q$ and $X \subseteq E(Q)$ and is called an elementary lift of $M$, if $|X|=1$. A splitting operation on a binary matroid can result…

Combinatorics · Mathematics 2023-01-06 Shital D. Solanki , Ganesh Mundhe , S. B. Dhotre

Networks are frequently studied algebraically through matrices. In this work, we show that networks may be studied in a more abstract level using results from the theory of matroids by establishing connections to networks by decomposition…

Combinatorics · Mathematics 2015-11-17 Konstantinos Papalamprou , Leonidas Pitsoulis

For a matroid $M$, an element $e$ such that both $M\backslash e$ and $M/e$ are regular is called a regular element of $M$. We determine completely the structure of non-regular matroids with at least two regular elements. Besides four small…

Combinatorics · Mathematics 2015-09-15 Sandra Kingan , Manoel Lemos

Let $M$ be a matroid and let $Q$, $R$, $S$ and $T$ be subsets of the ground set such that the smallest separation that separates $Q$ from $R$ has order $k$ and the smallest separation that separates $S$ from $T$ has order $l$. We prove that…

Combinatorics · Mathematics 2014-03-06 Rong Chen , Geoff Whittle