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Related papers: Canonical binary $\Delta$-matroids

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For an abelian group $\Gamma$, a $\Gamma$-labelled graph is a graph whose vertices are labelled by elements of $\Gamma$. We prove that a certain collection of edge sets of a $\Gamma$-labelled graph forms a delta-matroid, which we call a…

Combinatorics · Mathematics 2023-10-20 Donggyu Kim , Duksang Lee , Sang-il Oum

Positive geometries are semialgebraic sets equipped with a canonical differential form whose residues mirror the boundary structure of the geometry. Every full-dimensional projective polytope is a positive geometry. Motivated by the…

Combinatorics · Mathematics 2025-11-27 Christopher Eur , Thomas Lam

This paper is the continuation of the research of the author and his colleagues of the {\it canonical} decomposition of graphs. The idea of the canonical decomposition is to define the binary operation on the set of graphs and to represent…

Combinatorics · Mathematics 2016-07-19 Pavel Skums

We introduce a binary matroid M(IAS(G)) associated with a looped simple graph G. M(IAS(G)) classifies G up to local equivalence, and determines the delta-matroid and isotropic system associated with G. Moreover, a parametrized form of its…

Combinatorics · Mathematics 2014-11-11 Lorenzo Traldi

Delta-matroids are "type B" generalizations of matroids in the same way that maximal orthogonal Grassmannians are generalizations of Grassmannians. A delta-matroid analogue of the Tutte polynomial of a matroid is the interlace polynomial.…

Combinatorics · Mathematics 2024-09-19 Christopher Eur , Matt Larson , Hunter Spink

In contrast to matroids, vf-safe delta-matroids have three kinds of minors and are closed under the operations of twist and loop complementation. We show that the delta-matroids representable over GF(4) with respect to the nontrivial…

Combinatorics · Mathematics 2014-05-16 Robert Brijder , Hendrik Jan Hoogeboom

Blasiak verified a conjecture of White for graphic matroids by showing that the toric ideal of a graphic matroid is generated by quadrics. In this paper, we extend this result to frame matroids satisfying a linearity condition. Such classes…

Combinatorics · Mathematics 2020-04-10 Sean McGuinness

One of the most important classes of even $\Delta$-matroids arises from orientable ribbon graphs, which play a role analogous to that of graphic matroids in matroid theory. Motivated by a natural correspondence between strong…

Combinatorics · Mathematics 2026-03-09 Changxin Ding , Donggyu Kim

Canonical matrices of (a) bilinear and sesquilinear forms, (b) pairs of forms, in which every form is symmetric or skew-symmetric, and (c) pairs of Hermitian forms are given over finite fields of characteristic not 2 and over finite…

Representation Theory · Mathematics 2010-11-16 Vladimir V. Sergeichuk

Let $M$ be an arbitrary matroid with circuits $\mathcal{C}(M)$. We propose a definition of a derived matroid $\delta M$ that has as its ground set $\mathcal{C}(M)$. Unlike previous attempts of such a definition, our definition applies to…

Combinatorics · Mathematics 2022-12-22 Olga Kuznetsova , Ragnar Freij-Hollanti , Relinde Jurrius

One generalization of ordinary matroids is symplectic matroids. While symplectic matroids were initially defined by their collections of bases, there has been no cryptomorphic definition of symplectic matroids in terms of circuits. We give…

Combinatorics · Mathematics 2020-09-22 Zhexiu Tu

A recent line of research has concentrated on exploring the links between analytic and combinatorial theories of submodularity, uncovering several key connections between them. In this context, Lov\'asz initiated the study of matroids from…

Combinatorics · Mathematics 2024-10-16 Kristóf Bérczi , Márton Borbényi , László Lovász , László Márton Tóth

Stanley's symmetrized chromatic polynomial is a generalization of the ordinary chromatic polynomial to a graph invariant with values in a ring of polynomials in infnitely many variables. The ordinary chromatic polynomial is a specialization…

Combinatorics · Mathematics 2018-09-11 Marina Dudina , Vyacheslav Zhukov

We show that computing canonical representations for circular-arc (CA) graphs reduces to computing certain subsets of vertices called flip sets. For a broad class of CA graphs, which we call uniform, it suffices to compute a CA…

Data Structures and Algorithms · Computer Science 2018-02-02 Maurice Chandoo

This paper develops an invariant--geometric interpretation of the canonization problem for simple undirected weighted graphs based on the {discrete moving frame method} for finite groups. We consider the action of the {pair group}…

Combinatorics · Mathematics 2026-01-27 Leonid Bedratyuk

Dexterous manipulation policies today largely assume fixed hand designs, severely restricting their generalization to new embodiments with varied kinematic and structural layouts. To overcome this limitation, we introduce a parameterized…

Robotics · Computer Science 2026-05-19 Zhenyu Wei , Yunchao Yao , Mingyu Ding

We introduce a noncommutative binary operation on matroids, called free product. We show that this operation respects matroid duality, and has the property that, given only the cardinalities, an ordered pair of matroids may be recovered, up…

Combinatorics · Mathematics 2007-05-23 Henry Crapo , William Schmitt

In this note we introduce a sufficient condition for the Orlik-Solomon algebra associated to a matroid M to be l-adic and we prove that this condition is necessary when M is binary (in particular graphic). Moreover, this result cannot be…

Combinatorics · Mathematics 2007-05-23 Raul Cordovil , David Forge

In this paper we introduce valuated $\Delta$-matroids, a natural generalization of two objects of study in matroid theory: valuated matroids and $\Delta$-matroids. We show that these objects exhibit nice properties analogous to ordinary…

Combinatorics · Mathematics 2025-07-23 Nathan Cheung , Tracy Chin , Gaku Liu , Cynthia Vinzant

Cycle polytopes of matroids have been introduced in combinatorial optimization as a generalization of important classes of polyhedral objects like cut polytopes and Eulerian subgraph polytopes associated to graphs. Here we start an…

Combinatorics · Mathematics 2021-05-04 Tim Römer , Sara Saeedi Madani