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

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The ring of cyclic quasi-symmetric functions and its non-Escher subring are introduced in this paper. A natural basis consists of fundamental cyclic quasi-symmetric functions; for the non-Escher subring they arise as toric $P$-partition…

Combinatorics · Mathematics 2020-05-27 Ron M. Adin , Ira M. Gessel , Victor Reiner , Yuval Roichman

We use dual equivalence to give a short, combinatorial proof that Stanley symmetric functions are Schur positive. We introduce weak dual equivalence, and use it to give a short, combinatorial proof that Schubert polynomials are key…

Combinatorics · Mathematics 2017-02-15 Sami Assaf

We introduce a new basis for quasisymmetric functions, which arise from a specialization of nonsymmetric Macdonald polynomials to standard bases, also known as Demazure atoms. Our new basis is called the basis of quasisymmetric Schur…

Combinatorics · Mathematics 2010-11-30 J. Haglund , K. Luoto , S. Mason , S. van Willigenburg

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.…

Combinatorics · Mathematics 2023-11-14 Per Alexandersson , Ezgi Kantarci Oğuz

In this paper we prove a new version of Krein-Langer factorization theorem in the slice hyperholomorphic setting which is more general than the one proved in [D. Alpay, F. Colombo, I. Sabadini, Krein-Langer factorization and related topics…

Complex Variables · Mathematics 2014-06-27 Daniel Alpay , Fabrizio Colombo , Irene Sabadini

Formulas are obtained that express the Schur S-functions indexed by Young diagrams of rectangular shape as linear combinations of "mixed" products of Schur's S- and Q-functions. The proof is achieved by using representations of the affine…

Representation Theory · Mathematics 2007-05-23 Takeshi Ikeda , Hiroshi Mizukawa , Tatsuhiro Nakajima , Hiro-Fumi Yamada

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

We study a multi-symmetric generalization of the classical Schur functions called the multi-symmetric Schur functions. These functions form an integral basis for the ring of multi-symmetric functions indexed by tuples of partitions and are…

Combinatorics · Mathematics 2025-09-23 Milo Bechtloff Weising

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

In this thesis we prove Schur-positivity of certain graph families. In addition, we exlpor existence of cyclic descent extensions on several families of Schur-positive sets.

Combinatorics · Mathematics 2023-08-29 Yuval Khachatryan-Raziel

Classical Schur analysis is intimately connected to the theory of orthogonal polynomials on the circle [Simon, 2005]. We investigate here the connection between multipoint Schur analysis and orthogonal rational functions. Specifically, we…

Classical Analysis and ODEs · Mathematics 2010-02-11 L. Baratchart , S. Kupin , V. Lunot , M. Olivi

After deriving inequalities on coefficients arising in the expansion of a Schur $P$-function in terms of Schur functions we give criteria for when such expansions are multiplicity free. From here we study the multiplicity of an irreducible…

Combinatorics · Mathematics 2007-06-25 Kristin M. Shaw , Stephanie van Willigenburg

While equality of skew Schur functions is well understood, the problem of determining when two skew Schur $Q$ functions are equal is still largely open. It has been studied in the case of ribbon shapes in 2008 by Barekat and van…

Combinatorics · Mathematics 2021-08-27 Maria Gillespie , Kyle Salois

We study k-Schur functions characterized by k-tableaux, proving combinatorial properties such as a k-Pieri rule and a k-conjugation. This new approach relies on developing the theory of k-tableaux, and includes the introduction of a…

Combinatorics · Mathematics 2007-05-23 Luc Lapointe , Jennifer Morse

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

Using Schur positivity and the principal specialization of Schur functions, we provide a proof of a recent conjecture of Liu and Wang on the $q$-log-convexity of the Narayana polynomials, and a proof of the second conjecture that the…

Combinatorics · Mathematics 2008-06-11 William Y. C. Chen , Larry X. W. Wang , Arthur L. B. Yang

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 give a combinatorial rule for calculating the coefficients in the expansion of a product of two factorial Schur functions. It is a special case of a more general rule which also gives the coefficients in the expansion of a skew factorial…

q-alg · Mathematics 2008-02-03 Alexander I. Molev , Bruce E. Sagan

We introduce a shifted analog of the plactic monoid of Lascoux and Sch\"utzenberger, the \emph{shifted plactic monoid}. It can be defined in two different ways: via the \emph{shifted Knuth relations}, or using Haiman's mixed insertion.…

Combinatorics · Mathematics 2009-01-21 Luis Serrano

The Stanley-Stembridge conjecture associates a symmetric function to each natural unit interval order $\mathcal P$. In this paper, we define relations \`a la Knuth on the symmetric group for each $\mathcal P$ and conjecture that the…

Combinatorics · Mathematics 2020-05-15 Dongkwan Kim , Pavlo Pylyavskyy