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Related papers: Crystals and Schur $P$-positive expansions

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In the seminal work of Stanley, several conjectures were made on the structure of Littlewood-Richardson coefficients for the multiplication of Jack symmetric functions. Motivated by recent results of Alexandersson and the present author, we…

Combinatorics · Mathematics 2025-07-22 Ryan Mickler

For a $(3+1)$-free poset $P$, we define a hybrid of $P$-tableaux and cylindric tableaux called cylindric $P$-tableaux. We introduce $P$-analogs of cylindric Schur functions, defined by a determinantal formula, and prove that they are the…

Combinatorics · Mathematics 2022-11-10 Isaiah Siegl

Work of Grantcharov et al. develops a theory of abstract crystals for the queer Lie superalgebra $\mathfrak{q}_n$. Such $\mathfrak{q}_n$-crystals form a monoidal category in which the connected normal objects have unique highest weight…

Representation Theory · Mathematics 2024-02-01 Eric Marberg , Kam Hung Tong

The plethysm product of Schur functions corresponds to composing polynomial representations of infinite general linear groups. Finding the plethysm coefficients $\langle s_\nu \circ s_\mu, s_\lambda\rangle$ that express an arbitrary…

Combinatorics · Mathematics 2025-10-08 Rowena Paget , Mark Wildon

The Pieri rule expresses the product of a Schur function and a single row Schur function in terms of Schur functions. We extend the classical Pieri rule by expressing the product of a skew Schur function and a single row Schur function in…

Combinatorics · Mathematics 2012-02-01 Sami Assaf , Peter R. W. McNamara , Thomas Lam

We investigate chromatic symmetric functions in the relation to the algebra $\Gamma$ of symmetric functions generated by Schur $Q$-functions. We construct natural bases of $\Gamma$ in terms of chromatic symmetric functions. We also consider…

Combinatorics · Mathematics 2019-07-24 Soojin Cho , JiSun Huh , Sun-Young Nam

We apply crystal theory to affine Schubert calculus, Gromov-Witten invariants for the complete flag manifold, and the positroid stratification of the positive Grassmannian. We introduce operators on decompositions of elements in the…

Combinatorics · Mathematics 2016-06-02 Jennifer Morse , Anne Schilling

We apply a theorem of Geronimus to derive some new formulas connecting Schur functions with orthogonal polynomials on the unit circle. The applications include the description of the associated measures and a short proof of Boyd's result…

Classical Analysis and ODEs · Mathematics 2009-09-25 Feruenc Pinteŕ , Paul G. Nevai

We study a linear map on symmetric functions that ``divides'' a partition by a positive integer $k$, sending a Schur function indexed by a partition of $kn$ to a symmetric function indexed by partitions of $n$. We determine its Schur…

Combinatorics · Mathematics 2026-05-22 Per Alexandersson , Lilan Dai

Determining if a symmetric function is Schur-positive is a prevalent and, in general, a notoriously difficult problem. In this paper we study the Schur-positivity of a family of symmetric functions. Given a partition \lambda, we denote by…

Combinatorics · Mathematics 2013-10-11 Cristina Ballantine , Rosa Orellana

We use crystals of tableaux and descent compositions to understand the decomposition of Schur functions $s_\lambda$ into Gessel's fundamental quasisymmetric functions $F_\alpha$. The connected crystal of tableaux $B(\lambda)$, associated to…

Combinatorics · Mathematics 2023-02-16 Florence Maas-Gariépy

We obtain the Schur positivity of spider graphs of the forms $S(a,2,1)$ and $S(a,4,1)$, which are considered to have the simpliest structures for which the Schur positivity was unknown. The proof outline has four steps. First, we find…

Combinatorics · Mathematics 2023-05-16 Jean-Yves Thibon , David G. L. Wang

The machinery of noncommutative Schur functions is a general approach to Schur positivity of symmetric functions initiated by Fomin-Greene. Hwang recently adapted this theory to posets to give a new approach to the Stanley-Stembridge…

Combinatorics · Mathematics 2022-11-10 Jonah Blasiak , Holden Eriksson , Pavlo Pylyavskyy , Isaiah Siegl

The product $s_\mu s_\nu$ of two Schur functions is one of the most famous examples of a Schur-positive function, i.e. a symmetric function which, when written as a linear combination of Schur functions, has all positive coefficients. We…

Combinatorics · Mathematics 2007-05-23 Francois Bergeron , Peter McNamara

We introduce the edge Schur functions $E^{\lambda}$ that are defined as a generating series over edge labeled tableaux. We formulate $E^{\lambda}$ as the partition function for a solvable lattice model, which we use to show they are…

Combinatorics · Mathematics 2024-03-13 Ajeeth Gunna , Travis Scrimshaw

We give a Littlewood-Richardson type rule for expanding the product of a row-strict quasisymmetric Schur function and a symmetric Schur function in terms of row-strict quasisymmetric Schur functions. This expansion follows from several new…

Combinatorics · Mathematics 2011-02-09 Jeffrey Ferreira

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 2026-02-17 Per Alexandersson , James Haglund , George Wang

The Stanley-Stembridge conjecture asserts that the chromatic symmetric function of a $(3+1)$-free graph is $e$-positive. Recently, Hikita proved this conjecture by giving an explicit $e$-expansion of the Shareshian-Wachs $q$-chromatic…

Combinatorics · Mathematics 2025-04-10 Sean T. Griffin , Anton Mellit , Marino Romero , Kevin Weigl , Joshua Jeishing Wen

We consider the expansion of the square of a complete homogeneous function $h_\lambda$, or of an elementary symmetric function $e_\lambda$, in the basis of Schur functions. This square also decomposes into two plethysms, $s_2[h_\lambda]$…

Combinatorics · Mathematics 2022-03-17 Florence Maas-Gariépy , Étienne Tétreault

The immaculate functions, $\mathfrak{S}_{\alpha}$, were introduced as a Schur-like basis for $\operatorname{\mathsf{Nsym}}$. We investigate facts about their structure constants. These are analogues of Littlewood-Richardson coefficents. We…

Combinatorics · Mathematics 2021-10-12 Shu Xiao Li