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Related papers: Lattice path matroids: enumerative aspects and Tut…

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Fix two lattice paths $P$ and $Q$ from $(0,0)$ to $(m,r)$ that use East and North steps with $P $ never going above $Q$. Bonin et al. show that the lattice paths that go from $(0,0)$ to $(m,r)$ and remain bounded by $P$ and $Q$ can be…

Combinatorics · Mathematics 2012-12-27 Hoda Bidkhori

The configuration of a matroid $M$ is the abstract lattice of cyclic flats (flats that are unions of circuits) where we record the size and rank of each cyclic flat, but not the set. One can compute the Tutte polynomial of $M$, and stronger…

Combinatorics · Mathematics 2025-12-18 Joseph E. Bonin , Anna de Mier

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

$q$-Matroids are defined on complemented modular support lattices. Minors of length 2 are of four types as in a "classical" matroid. Tutte polynomials $\tau(x,y)$ of matroids are calculated either by recursion over deletion/contraction of…

Combinatorics · Mathematics 2017-07-13 Guus Bollen , Henry Crapo , Relinde Jurrius

We give a quantum-inspired $O(n^4)$ algorithm computing the Tutte polynomial of a lattice path matroid, where $n$ is the size of the ground set of the matroid. Furthermore, this can be improved to $O(n^2)$ arithmetic operations if we…

Combinatorics · Mathematics 2015-10-08 Jason Morton , Jacob Turner

Many important enumerative invariants of a matroid can be obtained from its Tutte polynomial, and many more are determined by two stronger invariants, the $\mathcal{G}$-invariant and the configuration of the matroid. We show that the same…

Combinatorics · Mathematics 2024-08-07 Joseph E. Bonin , Kevin Long

Let $M$ be a matroid without loops or coloops and let $T(M;x,y)$ be its Tutte polynomial. In 1999 Merino and Welsh conjectured that $$\max(T(M;2,0), T(M;0,2))\geq T(M;1,1)$$ holds for graphic matroids. Ten years later, Conde and Merino…

Combinatorics · Mathematics 2016-10-28 Kolja Knauer , Leonardo Martínez-Sandoval , Jorge Luis Ramírez Alfonsín

We show how the Tutte polynomial of a matroid $M$ can be computed from its condensed configuration, which is a statistic of its lattice of cyclic flats. The results imply that the Tutte polynomial of $M$ is already determined by the…

Combinatorics · Mathematics 2014-09-26 Jens Niklas Eberhardt

The Tutte polynomial for matroids is not directly applicable to polymatroids. For instance, deletion-contraction properties do not hold. We construct a polynomial for polymatroids which behaves similarly to the Tutte polynomial of a…

Combinatorics · Mathematics 2016-04-05 Amanda Cameron , Alex Fink

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

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

The Tutte polynomial is a significant invariant of graphs and matroids. It is well-known that it has three equivalent definitions: bases expansion, rank generating function, and deletion-contraction formula. The polymatroid Tutte polynomial…

Combinatorics · Mathematics 2025-10-14 Xiaxia Guan , Xian'an Jin , Weiling Yang

We describe a construction of the Tutte polynomial for both matroids and $q$-matroids based on an appropriate partition of the underlying support lattice into intervals that correspond to prime-free minors, which we call a Tutte partition.…

Combinatorics · Mathematics 2024-11-12 Eimear Byrne , Andrew Fulcher

The catenary data of a matroid $M$ of rank $r$ on $n$ elements is the vector $(\nu(M;a_0,a_1,\ldots,a_r))$, indexed by compositions $(a_0,a_1,\ldots,a_r)$, where $a_0 \geq 0$,\, $a_i > 0$ for $i \geq 1$, and $a_0+ a_1 + \cdots + a_r = n$,…

Combinatorics · Mathematics 2025-02-13 Joseph E. Bonin , Joseph P. S. Kung

We begin our analysis with the study of two collections of lattice paths in the plane, denoted $\mathcal{D}_{[n,i,j]}$ and $\mathcal{P}_{[n,i,j]}$. These paths consist of sequences of $n$ steps, where each step allows movement in three…

Combinatorics · Mathematics 2023-07-14 J. Kim , A. López-García , V. A. Prokhorov

The Tutte polynomial of a graph or a matroid, named after W. T. Tutte, has the important universal property that essentially any multiplicative graph or network invariant with a deletion and contraction reduction must be an evaluation of…

Combinatorics · Mathematics 2012-03-02 Criel Merino , Marcelino Ramírez-Ibáñez , Guadalupe Rodríguez Sanchez

We show that in an ordered matroid the partial derivative \partial^{p+q}t/\partialx^p\partialyq of the Tutte polynomial is p!q! times the generating function of activities of subsets with corank p and nullity q. More generally, this…

Combinatorics · Mathematics 2012-05-24 Michel Las Vergnas

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

We show that computing the Tutte polynomial of a linear matroid of dimension $k$ on $k^{O(1)}$ points over a field of $k^{O(1)}$ elements requires $k^{\Omega(k)}$ time unless the \#ETH---a counting extension of the Exponential Time…

Computational Complexity · Computer Science 2020-07-29 Andreas Björklund , Petteri Kaski

We show that the 4-variable generating function of certain orientation related parameters of an ordered oriented matroid is the evaluation at (x + u, y+v) of its Tutte polynomial. This evaluation contains as special cases the counting of…

Combinatorics · Mathematics 2012-05-25 Michel Las Vergnas
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