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Related papers: Combinatorial expansions in K-theoretic bases

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Let $\Lambda$ be the space of symmetric functions and $V_k$ be the subspace spanned by the modified Schur functions $\{S_\lambda[X/(1-t)]\}_{\lambda_1\leq k}$. We introduce a new family of symmetric polynomials,…

Quantum Algebra · Mathematics 2007-05-23 L. Lapointe , A. Lascoux , J. Morse

We study the space, $R_m$, of $m$-symmetric functions consisting of polynomials that are symmetric in the variables $x_{m+1},x_{m+2},x_{m+3},\dots$ but have no special symmetry in the variables $x_1,\dots,x_m$. We obtain $m$-symmetric…

Combinatorics · Mathematics 2025-01-10 Luc Lapointe

The ring of symmetric functions $\Lambda$, with natural basis given by the Schur functions, arise in many different areas of mathematics. For example, as the cohomology ring of the grassmanian, and as the representation ring of the…

Combinatorics · Mathematics 2009-09-03 Robin Langer

We give geometric descriptions of the category C_k(n,d) of rational polynomial representations of GL_n over a field k of degree d for d less than or equal to n, the Schur functor and Schur-Weyl duality. The descriptions and proofs use a…

Representation Theory · Mathematics 2014-02-07 Carl Mautner

Let $k$ be a commutative $\mathbb{Q}$-algebra. We study families of functors between categories of finitely generated $R$-modules which are defined for all commutative $k$-algebras $R$ simultaneously and are compatible with base changes.…

Category Theory · Mathematics 2020-01-29 Martin Brandenburg

Schur functions are a basis of the symmetric function ring that represent Schubert cohomology classes for Grassmannians. Replacing the cohomology ring with $K$-theory yields a rich combinatorial theory of inhomogeneous deformations, where…

Combinatorics · Mathematics 2023-05-19 Logan Crew , Oliver Pechenik , Sophie Spirkl

We study Type C $K$-Stanley symmetric functions, which are $K$-theoretic extensions of the Type C Stanley symmetric functions. They are indexed by signed permutations and can be used to enumerate reduced words via their expansion into Schur…

Combinatorics · Mathematics 2025-03-24 Joshua Arroyo , Zachary Hamaker , Graham Hawkes , Jianping Pan

For a skew shape $\lambda/\mu$, we define the hybrid Grothendieck polynomial $${G}_{\lambda/\mu}(\textbf{x};\textbf{t};\textbf{w}) =\sum_{T\in \mathrm{SVRPP}(\lambda/\mu)} \textbf{x}^{\mathrm{ircont}(T)}\textbf{t}^{\mathrm{ceq}…

Combinatorics · Mathematics 2025-05-27 Peter L. Guo , Mingyang Kang , Jiaji Liu

We introduce explicit combinatorial interpretations for the coefficients in some of the transition matrices relating to skew Hall-Littlewood polynomials P_lambda/mu(x;t) and Hivert's quasisymmetric Hall-Littlewood polynomials G_gamma(x;t).…

Combinatorics · Mathematics 2013-06-20 Nicholas A. Loehr , Luis G. Serrano , Gregory S. Warrington

Kostka functions $K^{\pm}_{\lambda, \mu}(t)$ associated to complex reflection groups are a generalization of Kostka polynomials, which are indexed by a pair $\lambda, \mu$ of $r$-partitions and a sign $+, -$. It is expected that there…

Representation Theory · Mathematics 2015-09-25 Toshiaki Shoji

The machinery of noncommutative Schur functions provides a general tool for obtaining Schur expansions for combinatorially defined symmetric functions. We extend this approach to a wider class of symmetric functions, explore its strengths…

Combinatorics · Mathematics 2016-07-12 Jonah Blasiak , Sergey Fomin

We consider a type of divided symmetrization $\overrightarrow{D}_{\lambda,G}$ where $\lambda$ is a nonincreasing partition on $n$ and where $G$ is a graph. We discover that in the case where $\lambda$ is a hook shape partition with first…

Combinatorics · Mathematics 2019-08-27 Nate Ince

We introduce new families of cylindric symmetric functions as subcoalgebras in the ring of symmetric functions $\Lambda$ (viewed as a Hopf algebra) which have non-negative structure constants. Combinatorially these cylindric symmetric…

Combinatorics · Mathematics 2019-07-05 Christian Korff , David Palazzo

The dual stable Grothendieck polynomials are a deformation of the Schur functions, originating in the study of the K-theory of the Grassmannian. We generalize these polynomials by introducing a countable family of additional parameters, and…

Combinatorics · Mathematics 2020-09-29 Pavel Galashin , Darij Grinberg , Gaku Liu

We present positivity conjectures for the Schur expansion of Jack symmetric functions in two bases given by binomial coefficients. Partial results suggest that there are rich combinatorics to be found in these bases, including Eulerian…

Combinatorics · Mathematics 2019-07-02 Per Alexandersson , James Haglund , George Wang

The Schur polynomials $s_{\lambda}$ are essential in understanding the representation theory of the general linear group. They also describe the cohomology ring of the Grassmannians. For $\rho = (n, n-1, \dots, 1)$ a staircase shape and…

Combinatorics · Mathematics 2021-10-05 Fiona Abney-McPeek , Serena An , Jakin Ng

Fulton's universal Schubert polynomials give cohomology formulas for a class of degeneracy loci, which generalize Schubert varieties. The K-theoretic quiver formula of Buch expresses the structure sheaves of these loci as integral linear…

Combinatorics · Mathematics 2016-09-07 Anders Skovsted Buch , Andrew Kresch , Harry Tamvakis , Alexander Yong

This paper uses the theory of dual equivalence graphs to give explicit Schur expansions for several families of symmetric functions. We begin by giving a combinatorial definition of the modified Macdonald polynomials and modified…

Combinatorics · Mathematics 2015-08-31 Austin Roberts

We introduce two families of symmetric functions with an extra parameter t that specialize to Schubert representatives for cohomology and homology of the affine Grassmannian when t = 1. The families are defined by a statistic on…

Combinatorics · Mathematics 2016-05-17 Avinash J. Dalal , Jennifer Morse

We introduce and study a generalization $s_{(\mu|\lambda)}$ of the Schur functions called the almost symmetric Schur functions. These functions simultaneously generalize the finite variable key polynomials and the infinite variable Schur…

Combinatorics · Mathematics 2024-05-03 Milo Bechtloff Weising