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Related papers: Matroid and Tutte-connectivity in infinite graphs

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We provide a unique decomposition of every 4-connected graph into parts that are either quasi-5-connected, cycles of triangle-torsos and 3-connected torsos on $\leq 5$ vertices, generalised double-wheels, or thickened $K_{4,m}$'s. The…

Combinatorics · Mathematics 2026-02-12 Jan Kurkofka , Tim Planken

The Tutte polynomial is a fundamental invariant of graphs and matroids. In this article, we define a generalization of the Tutte polynomial to oriented graphs and regular oriented matroids. To any regular oriented matroid $N$, we associate…

Combinatorics · Mathematics 2023-10-12 Jordan Awan , Olivier Bernardi

We provide a full classification of all families of matroids that are closed under duality and minors, and for which the Tutte polynomial is a universal valuative invariant. There are four inclusion-wise maximal families, two of which are…

Combinatorics · Mathematics 2025-02-10 Luis Ferroni , Benjamin Schröter

We characterise all vertex-transitive finite connected graphs as essentially 5-connected or on a short list of explicit graph-classes. Our proof heavily uses Tutte-type canonical decompositions.

Combinatorics · Mathematics 2026-02-11 Jan Kurkofka , Tim Planken

We consider the class of graphs for which the edge connectivity is equal to the maximum number of edge-disjoint spanning trees, and the natural generalization to matroids, where the cogirth is equal to the number of disjoint bases. We…

Combinatorics · Mathematics 2014-02-10 Robert F. Bailey , Mike Newman , Brett Stevens

We characterize the class of infinite connected graphs $ G $ for which there exists a $ T $-join for any choice of an infinite $ T \subseteq V(G) $. We also show that the following well-known fact remains true in the infinite case. If $ G $…

Combinatorics · Mathematics 2017-04-25 Attila Joó

The Tutte polynomial is a fundamental invariant associated to a graph, matroid, vector arrangement, or hyperplane arrangement. This short survey focuses on some of the most important results on Tutte polynomials of hyperplane arrangements.…

Combinatorics · Mathematics 2017-10-05 Federico Ardila

Answering a question of Diestel, we develop a topological notion of gammoids in infinite graphs which, unlike traditional infinite gammoids, always define a matroid. As our main tool, we prove for any infinite graph $G$ with vertex sets $A$…

Combinatorics · Mathematics 2014-04-02 Johannes Carmesin

Graphings serve as limit objects for bounded-degree graphs. We define the ``cycle matroid'' of a graphing as a submodular setfunction, with values in [0,1], which generalizes (up to normalization) the cycle matroid of finite graphs. We…

Combinatorics · Mathematics 2023-11-08 László Lovász

We prove that every 3-connected 2-indivisible infinite planar graph has a 1-way infinite 2-walk. (A graph is 2-indivisible if deleting finitely many vertices leaves at most one infinite component, and a 2-walk is a spanning walk using every…

Combinatorics · Mathematics 2015-08-28 Daniel P. Biebighauser , M. N. Ellingham

We study algebraic properties of the Tutte polynomial of a matroid and its generalizations to other combinatorially defined bivariate polynomial invariants. Merino, de Mier and Noy showed that the Tutte polynomial of a connected matroid is…

Combinatorics · Mathematics 2025-10-08 Andrew Goodall , Florent Jouve , Jean-Sébastien Sereni

The Tutte polynomial is a well-studied invariant of graphs and matroids. We first extend the Tutte polynomial from graphs to hypergraphs, and more generally from matroids to polymatroids, as a two-variable polynomial. Our definition is…

Combinatorics · Mathematics 2020-07-23 Olivier Bernardi , Tamas Kalman , Alex Postnikov

The mutually enriching relationship between graphs and matroids has motivated discoveries in both fields. In this paper, we exploit the similar relationship between embedded graphs and delta-matroids. There are well-known connections…

Combinatorics · Mathematics 2019-03-04 Carolyn Chun , Iain Moffatt , Steven D. Noble , Ralf Rueckriemen

A seminal result by Whitney describes when two graphs have the same cycles. We consider the analogous problem for even cycle matroids. A representation of an even cycle matroid is a pair formed by a graph together with a special set of…

Combinatorics · Mathematics 2011-09-15 Bertrand Guenin , Irene Pivotto , Paul Wollan

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

Given two graphs, a mapping between their edge-sets is cycle-continuous, if the preimage of every cycle is a cycle. The motivation for this notion is Jaeger's conjecture that for every bridgeless graph there is a cycle-continuous mapping to…

Combinatorics · Mathematics 2013-01-01 Robert Šámal

Brylawski proved the coefficients of the Tutte polynomial of a matroid satisfy a set of linear relations. We extend these relations to a generalization of the Tutte polynomial that includes greedoids and antimatroids. This leads to families…

Combinatorics · Mathematics 2014-05-16 Gary Gordon

For each $n\ge 14$, we provide an example of a linklessly embeddable, Tutte-4-connected graph of order $n$.

Combinatorics · Mathematics 2021-06-16 Andrei Pavelescu , Elena Pavelescu

The Tutte polynomial is the most general invariant of matroids and graphs that can be computed recursively by deleting and contracting edges. We generalize this invariant to any class of combinatorial objects with deletion and contraction…

Combinatorics · Mathematics 2019-02-04 Clément Dupont , Alex Fink , Luca Moci

A {\em connectivity function} on a set $E$ is a function $\lambda:2^E\rightarrow \mathbb R$ such that $\lambda(\emptyset)=0$, that $\lambda(X)=\lambda(E-X)$ for all $X\subseteq E$, and that $\lambda(X\cap Y)+\lambda(X\cup Y)\leq…

Combinatorics · Mathematics 2020-07-10 Nathan Bowler , Susan Jowett