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Related papers: Interlacement and Activities in Delta-Matroids

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Matroid theory is often thought of as a generalization of graph theory. In this paper we propose an analogous correspondence between embedded graphs and delta-matroids. We show that delta-matroids arise as the natural extension of graphic…

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

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

The weighted transition polynomial of a multimatroid is a generalization of the Tutte polynomial. By defining the activity of a skew class with respect to a basis in a multimatroid, we obtain an activities expansion for the weighted…

Combinatorics · Mathematics 2025-02-24 Criel Merino , Iain Moffatt , Steven Noble

We provide a unified framework in which the interlace polynomial and several related graph polynomials are defined more generally for multimatroids and delta-matroids. Using combinatorial properties of multimatroids rather than…

Combinatorics · Mathematics 2014-03-26 Robert Brijder , Hendrik Jan Hoogeboom

In this paper, we survey results regarding the interlace polynomial of a graph, connections to such graph polynomials as the Martin and Tutte polynomials, and generalizations to the realms of isotropic systems and delta-matroids.

Combinatorics · Mathematics 2016-01-13 Ada Morse

Multimatroids generalize matroids, delta-matroids, and isotropic systems, and transition polynomials of multimatroids subsume various polynomials for these latter combinatorial structures, such as the interlace polynomial and the…

Combinatorics · Mathematics 2017-08-18 Robert Brijder

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 this work, we study the interlace polynomial as a generalization of a graph invariant to delta-matroids. We prove that the interlace polynomial satisfies the four-term relation for delta-matroids and determines thus a finite type…

Combinatorics · Mathematics 2020-03-02 Nadezhda Kodaneva

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

To a singular knot K with n double points, one can associate a chord diagram with n chords. A chord diagram can also be understood as a 4-regular graph endowed with an oriented Euler circuit. L. Traldi introduced a polynomial invariant for…

Combinatorics · Mathematics 2025-09-23 Alexander Dunaykin , Vyacheslav Zhukov

Given a 4-regular graph $F$, we introduce a binary matroid $M_{\tau}(F)$ on the set of transitions of $F$. Parametrized versions of the Tutte polynomial of $M_{\tau}(F)$ yield several well-known graph and knot polynomials, including the…

Combinatorics · Mathematics 2015-07-01 Lorenzo Traldi

Recently, Gross, Mansour and Tucker introduced the partial duality polynomial of a ribbon graph and posed a conjecture that there is no orientable ribbon graph whose partial duality polynomial has only one non-constant term. We found an…

Combinatorics · Mathematics 2021-08-04 Qi Yan , Xian'an Jin

We introduce a notion of duality (due to Brylawski) that generalizes matroid duality to arbitrary rank functions. This generalized duality allows for generalized operations (deletion and contraction) and a generalized polynomial based on…

Combinatorics · Mathematics 2012-01-10 Gary Gordon

There are several different extensions of the Tutte polynomial to graphs embedded in surfaces. To help frame the different options, here we consider the problem of extending the Tutte polynomial to cellularly embedded graphs starting from…

Combinatorics · Mathematics 2025-02-24 Iain Moffatt

Slater introduced the point-addition operation on graphs to classify 4-connected graphs. The $\Gamma$-extension operation on binary matroids is a generalization of the point-addition operation. In this paper, we obtain necessary and…

Combinatorics · Mathematics 2018-12-05 Y. M. Borse , Ganesh Mundhe

We define 2-decompositions of ribbon graphs, which generalise 2-sums and tensor products of graphs. We give formulae for the Bollobas-Riordan polynomial of such a 2-decomposition, and derive the classical Brylawski formula for the Tutte…

Combinatorics · Mathematics 2012-03-01 Stephen Huggett , Iain Moffatt

The interior and exterior activities of bases of a matroid are well-known notions that for instance permit one to define the Tutte polynomial. Recently, we have discovered correspondences between the regions of gainic hyperplane…

Combinatorics · Mathematics 2023-03-24 Rigoberto Flórez , David Forge

Vassiliev (finite type) invariants of knots can be described in terms of weight systems. These are functions on chord diagrams satisfying so-called 4-term relations. In the study of the sl2 weight system, it was shown that its value on a…

Combinatorics · Mathematics 2016-02-02 Sergey Lando , Vyacheslav Zhukov

Brylawski's tensor product formula expresses the Tutte polynomial of the tensor product of two graphs in terms of Tutte polynomials arising from the tensor factors. We are concerned with extensions of Brylawski's tensor product formula to…

Combinatorics · Mathematics 2023-09-04 Iain Moffatt , Steven Noble , Maya Thompson

In this note we generalize the convolution formula for the Tutte polynomial of Kook-Reiner-Stanton and Etienne-Las Vergnas to a more general setting that includes both arithmetic matroids and delta-matroids. As corollaries, we obtain new…

Combinatorics · Mathematics 2017-04-24 Spencer Backman , Matthias Lenz
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