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Related papers: Excluded minors for the class of split matroids

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We extend the splitting operation from binary matroids (Raghunathan et al., 1998) to $p$- matroids, where $p$-matroids refer to matroids representable over $GF(p).$ We also characterize circuits, bases, and independent sets of the resulting…

Combinatorics · Mathematics 2025-07-15 Prashant Malavadkar , Uday Jagadale , Sachin Gunjal

We call a class $\mathcal{M}$ of matroids hereditary if it is closed under flats. We denote by $\mathcal{M}^{ext}$ the class of matroids $M$ that is in $\mathcal{M}$, or has an element $e$ such that $M \backslash e$ is in $\mathcal{M}$. We…

Combinatorics · Mathematics 2024-11-21 Jagdeep Singh , Vaidy Sivaraman

We introduce the minor-closed, dual-closed class of multi-path matroids. We give a polynomial-time algorithm for computing the Tutte polynomial of a multi-path matroid, we describe their basis activities, and we prove some basic structural…

Combinatorics · Mathematics 2024-08-07 Joseph E. Bonin , Omer Gimenez

The Splitter Theorem states that, if $N$ is a 3-connected proper minor of a 3-connected matroid $M$ such that, if $N$ is a wheel or whirl then $M$ has no larger wheel or whirl, respectively, then there is a sequence $M_0,..., M_n$ of…

Combinatorics · Mathematics 2015-09-15 S. R. Kingan , Manoel Lemos

Zaslavsky introduced the concept of lifted-graphic matroid. For binary matroids, a binary elementary lift can be defined in terms of the splitting operation. In this paper, we give a method to get a forbidden-minor characterization for the…

Combinatorics · Mathematics 2019-10-15 Ganesh Mundhe , Y. M. Borse , K. V. Dalvi

We introduce the notion of a quasi-matroidal class of ordered simplicial complexes: an approximation to the idea of a matroid cryptomorphism in the landscape of ordered simplicial complexes. A quasi-matroidal class contains pure shifted…

Combinatorics · Mathematics 2016-08-16 Jose Alejandro Samper

We prove that the ranks of the subsets and the activities of the bases of a matroid define valuations for the subdivisions of a matroid polytope into smaller matroid polytopes.

Combinatorics · Mathematics 2019-08-15 Federico Ardila , Alex Fink , Felipe Rincón

Seymour's Splitter Theorem is a basic inductive tool for dealing with $3$-connected matroids. This paper proves a generalization of that theorem for the class of $2$-polymatroids. Such structures include matroids, and they model both sets…

Combinatorics · Mathematics 2017-06-27 James Oxley , Charles Semple , Geoff Whittle

If S is a set of matroids, then the matroid M is S-fragile if, for every element e in E(M), either M\e or M/e has no minor isomorphic to a member of S. Excluded-minor characterizations often depend, implicitly or explicitly, on…

Combinatorics · Mathematics 2015-05-01 Carolyn Chun , Deborah Chun , Dillon Mayhew , Stefan H. M. van Zwam

This study aims to shed light on new (sub)classes of matroids originating from cluster algebras and investigate their properties. We focus on what we call cluster matroids and build some results on them. Then, we point out a relationship…

Combinatorics · Mathematics 2025-06-23 Fayadh Kadhem

Given two finite matroids on the same ground set, a celebrated result of Edmonds says that the ground set can be partitioned into two disjoint subsets in a manner that there is a common independent set in both matroids whose intersection…

Combinatorics · Mathematics 2025-01-27 Irfan Alam

A simple binary matroid is called claw-free if none of its rank-3 flats are independent sets. These objects can be equivalently defined as the sets $E$ of points in $\mathrm{PG}(n-1,2)$ for which $|E \cap P|$ is not a basis of $P$ for any…

Combinatorics · Mathematics 2018-08-01 Peter Nelson , Kazuhiro Nomoto

A matroid is a combinatorial structure that captures and generalizes the algebraic concept of linear independence under a broader and more abstract framework. Matroids are closely related with many other topics in discrete mathematics, such…

Combinatorics · Mathematics 2022-03-16 Gianira N. Alfarano , Karan Khathuria , Simran Tinani

The weak-map order on the matroid base polytopes is the partial order defined by inclusion. Lucas proved that the base polytope of no binary matroid includes the base polytope of a connected matroid. A matroid base polytope is said to be…

Combinatorics · Mathematics 2012-03-26 Kenji Kashiwabara

Based on the notion of vectors and linear subspaces for a matroid, we develop a theory of flats and hyperplane arrangements for T-matroids, where T is a tract. This leads to several cryptomorphic descriptions of T-matroids: in terms of its…

Combinatorics · Mathematics 2026-03-11 Jannis Koulman , Oliver Lorscheid

Our splitter theorem for internally 4-connected binary matroids studies pairs of the form (M,N), where N and M are internally 4-connected binary matroids, M has a proper N-minor, and if M' is an internally 4-connected matroid such that M…

Combinatorics · Mathematics 2016-07-13 Carolyn Chun , Dillon Mayhew , James Oxley

We use counting arguments to show that asymptotically almost all sparse paving matroids contain an $H$-minor, where $H$ falls into one of several simple classes of matroids. Furthermore the result holds for all $H$ in a larger class of…

Combinatorics · Mathematics 2016-05-10 Will Critchlow

This article is a survey of matroid theory aimed at algebraic geometers. Matroids are combinatorial abstractions of linear subspaces and hyperplane arrangements. Not all matroids come from linear subspaces; those that do are said to be…

Algebraic Geometry · Mathematics 2014-09-12 Eric Katz

We classify all matroids with at most 8 elements that have the half-plane property, and we provide a list of some matroids on 9 elements that have, and that do not have the half-plane property. Furthermore, we prove that several classes of…

Combinatorics · Mathematics 2023-10-25 Mario Kummer , Büşra Sert

Splitting operation in Matroid Theory does not preserve graphicness, connectedness, cographicness, etc. Also, the splitting of binary gammoid does not necessarily be binary gammoid after splitting. We have characterized a class of graphic…

Combinatorics · Mathematics 2023-10-06 S. D. Solanki , S. B. Dhotre