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A catalogue of all non-isomorphic simple connected regular matroids ${\cal M}$ of cardinality $n \leq 15$ is provided on the net. These matroids are given as binary matrix matroids and are sieved from the large pool of all non-isomorphic…

Combinatorics · Mathematics 2011-07-08 Harald Fripertinger , Marcel Wild

We recover the Tutte polynomial of a matroid, up to change of coordinates, from an Ehrhart-style polynomial counting lattice points in the Minkowski sum of its base polytope and scalings of simplices. Our polynomial has coefficients of…

Combinatorics · Mathematics 2018-02-28 Amanda Cameron , Alex Fink

The multivariate arithmetic Tutte polynomial of arithmetic matroids is a generalization of the multivariate Tutte polynomial of matroids. In this note, we give the convolution formulas for the multivariate arithmetic Tutte polynomial of the…

Combinatorics · Mathematics 2023-10-10 Tianlong Ma , Xian'an Jin , Weiling Yang

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

In the paper [Proceedings of the Japan Academy, Ser. A Mathematical Sciences, 95(10) 111-113], the authors introduce the concept of the Tutte polynomials of genus $g$ and announce that each matroid $M$ can be reconstructed from its Tutte…

Combinatorics · Mathematics 2024-02-13 Tsuyoshi Miezaki , Manabu Oura , Tadashi Sakuma , Hidehiro Shinohara

The multivariate Tutte polynomial $\hat Z_M$ of a matroid $M$ is a generalization of the standard two-variable version, obtained by assigning a separate variable $v_e$ to each element $e$ of the ground set $E$. It encodes the full structure…

Combinatorics · Mathematics 2012-05-25 Adam Bohn , Peter J. Cameron , Peter Müller

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

We prove that the Tutte polynomial of a coloopless paving matroid is convex along the portions of the line segments x+y=p lying in the positive quadrant. Every coloopless paving matroids is in the class of matroids which contain two…

Combinatorics · Mathematics 2010-04-16 L. E. Chavez-Lomelí , C. Merino , S. D. Noble , M. Ramírez-Ibañez

We introduce and investigate multivariate Tutte polynomials, dichromatic polynomials, subset-corank polynomials, size-corank polynomials, and rank generating polynomials of semimatroids, which generalize the corresponding polynomial…

Combinatorics · Mathematics 2025-08-04 Houshan Fu

The Tutte polynomial is a well-studied invariant of matroids. The polymatroid Tutte polynomial $\mathcal{J}_{P}(x,y)$, introduced by Bernardi et al., is an extension of the classical Tutte polynomial from matroids to polymatroids $P$. In…

Combinatorics · Mathematics 2022-07-12 Xiaxia Guan , Weiling Yang , Xian'an Jin

We introduce a new matroid (graph) invariant, the arboricity polynomial. Given a matroid, the arboricity polynomial enumerates the number of covers of the ground set by disjoint independent sets. We establish the polynomiality of the…

Combinatorics · Mathematics 2025-05-09 Felix Breuer , Caroline J Klivans

We introduce a connectivity function for infinite matroids with properties similar to the connectivity function of a finite matroid, such as submodularity and invariance under duality. As an application we use it to extend Tutte's linking…

Combinatorics · Mathematics 2011-01-31 Henning Bruhn , Paul Wollan

The number of homomorphisms from a finite graph $F$ to the complete graph $K_n$ is the evaluation of the chromatic polynomial of $F$ at $n$. Suitably scaled, this is the Tutte polynomial evaluation $T(F;1-n,0)$ and an invariant of the cycle…

Combinatorics · Mathematics 2016-02-25 Andrew Goodall , Guus Regts , Lluis Vena

We begin with a review of Tutte's homotopy theory, which concerns the structure of certain graph associated to a matroid (together with some extra data). Concretely, Tutte's path theorem asserts that this graph is connected, and his…

Combinatorics · Mathematics 2026-01-21 Matthew Baker , Tong Jin , Oliver Lorscheid

Tutte's dichromate T(x,y) is a well known graph invariant. Using the original definition in terms of internal and external activities as our point of departure, we generalize the valuations T(x,1) and T(1,y) to hypergraphs. In the…

Combinatorics · Mathematics 2011-03-08 Tamás Kálmán

This paper studies the properties of two kinds of matroids: (a) algebraic matroids and (b) finite and infinite matroids whose ground set have some canonical symmetry, for example row and column symmetry and transposition symmetry. For (a)…

Combinatorics · Mathematics 2013-12-16 Franz J. Király , Zvi Rosen , Louis Theran

We introduce the ``trivariate Tutte polynomial" of a signed graph as an invariant of signed graphs up to vertex switching that contains among its evaluations the number of proper colorings and the number of nowhere-zero flows. In this, it…

Combinatorics · Mathematics 2022-03-01 Andrew Goodall , Bart Litjens , Guus Regts , Lluis Vena

We introduce the active partition of the ground set of an oriented matroid perspective (or quotient, or strong map) on a linearly ordered ground set. The reorientations obtained by arbitrarily reorienting parts of the active partition share…

Combinatorics · Mathematics 2018-07-19 Emeric Gioan

Let $M$ be a representable matroid, and $Q, R, S, T$ subsets of the ground set. We prove that, if $M$ is sufficiently large, then there is an element $e$ such that deleting or contracting $e$ preserves both the $Q$-$R$ and the $S$-$T$…

Combinatorics · Mathematics 2018-01-16 Tony Huynh , Stefan van Zwam

Let $G$ be a matrix and $M(G)$ be the matroid defined by linear dependence on the set $E$ of column vectors of $G.$ Roughly speaking, a parcel is a subset of pairs $(f,g)$ of functions defined on $E$ to an Abelian group $A$ satisfying a…

Combinatorics · Mathematics 2011-12-06 Joseph P. S. Kung