Zobrazeno 1 - 10
of 121
pro vyhledávání: '"Alexandersson, Per"'
Autor:
Alexandersson, Per, Jal, Aryaman
We define and study rook matroids, the bases of which correspond to non-nesting rook placements on a skew Ferrers board. We show that rook matroids are closed under taking duals, direct sums but not minors. Rook matroids are also transversal, positro
Externí odkaz:
http://arxiv.org/abs/2410.00127
A linear differential operator $T=Q(z)\frac{d}{dz}+P(z)$ with polynomial coefficients defines a continuous family of Hutchinson operators when acting on the space of positive powers of linear forms. In this context, $T$ has a unique minimal Hutchinso
Externí odkaz:
http://arxiv.org/abs/2406.10963
Autor:
Alexandersson, Per, Nabawanda, Olivia
The $(P, w)$-partition generating function $K_{(P,w)}(x)$ is a quasisymmetric function obtained from a labeled poset. Recently, Liu and Weselcouch gave a formula for the coefficients of $K_{(P,w)}(x)$ when expanded in the quasisymmetric power sum fun
Externí odkaz:
http://arxiv.org/abs/2405.19932
Given a linear ordinary differential operator T with polynomial coefficients, we study the class of closed subsets of the complex plane such that T sends any polynomial (resp. any polynomial of degree exceeding a given positive integer) with all root
Externí odkaz:
http://arxiv.org/abs/2404.14365
We generalize several classical results about Schur functions to the family of cylindric Schur functions. First, we give a combinatorial proof of a Murnaghan--Nakayama formula for expanding cylindric Schur functions in the power-sum basis. We also ex
Externí odkaz:
http://arxiv.org/abs/2311.07382
Autor:
Alexandersson, Per, Mickler, Ryan
We make progress towards understanding the structure of Littlewood-Richardson coefficients $g_{\lambda,\mu}^{\nu}$ for products of Jack symmetric functions. Building on recent results of the second author, we are able to prove new cases of a conjectu
Externí odkaz:
http://arxiv.org/abs/2309.13870
Publikováno v:
Discrete & Computational Geometry, 2024
We show that the polytopes obtained from the Birkhoff polytope by imposing additional inequalities restricting the "longest increasing subsequence" have Ehrhart quasi-polynomials which are honest polynomials, even though they are just rational polyto
Externí odkaz:
http://arxiv.org/abs/2206.02276
Publikováno v:
Journal of Differential Equations 391, (2024) 265-320
In this paper, we initiate the study of a new interrelation between linear ordinary differential operators and complex dynamics which we discuss in details in the simplest case of operators of order $1$. Namely, assuming that such an operator $T$ has
Externí odkaz:
http://arxiv.org/abs/2202.10197
Publikováno v:
Journal of Integer Sequences, Vol. 26 (2023), Article 23.4.2
We study a subset of permutations, where entries are restricted to having the same remainder as the index, modulo some integer $k \geq 2$. We show that when also imposing the classical 132- or 213-avoidance restriction on the permutations, we recover
Externí odkaz:
http://arxiv.org/abs/2201.08168
Publikováno v:
In Journal of Differential Equations 15 May 2024 391:265-320