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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

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

The fundamental quasisymmetric functions in superspace are a generalization of the fundamental quasisymmetric functions involving anticommuting variables. We obtain the action of the product, coproduct, and antipode on the fundamental…

Combinatorics · Mathematics 2024-11-21 Susanna Fishel , Jessica Gatica , Luc Lapointe , Maria Elena Pinto

We study the commutation relations and normal ordering between families of operators on symmetric functions. These operators can be naturally defined by the operations of multiplication, Kronecker product, and their adjoints. As…

Combinatorics · Mathematics 2020-04-14 Emmanuel Briand , Peter R. W. McNamara , Rosa Orellana , Mercedes Rosas

If we consider previously introduced extensions of Stanley's chromatic symmetric function $X_{G}(x_1, x_2, \ldots)$ for a graph $G$ to elements in the algebra $\textsf{QSym}$ of quasisymmetric functions and in the algebra $\textsf{NCSym}$…

Combinatorics · Mathematics 2024-10-08 John M. Campbell

We construct a new operation among representations of the symmetric group that interpolates between the classical internal and external products, which are defined in terms of tensor product and induction of representations. Following…

Combinatorics · Mathematics 2007-05-23 Marcelo Aguiar , Walter Ferrer , Walter Moreira

Recent work on recurrence in quantum walks has provided a representation of Schur functions in terms of unitary operators. We propose a generalization of Schur functions by extending this operator representation to arbitrary operators on…

Functional Analysis · Mathematics 2017-02-23 F. Alberto Grünbaum , Luis Velázquez

We provide direct proofs of product and coproduct formulae for Schur functions where the coefficients (Littlewood--Richardson coefficients) are defined as counting puzzles. The product formula includes a second alphabet for the Schur…

Mathematical Physics · Physics 2009-01-16 P. Zinn-Justin

It is known that the Schur expansion of a skew Schur function runs over the interval of partitions, equipped with dominance order, defined by the least and the most dominant Littlewood-Richardson filling of the skew shape. We characterise…

Combinatorics · Mathematics 2018-08-17 Olga Azenhas , Alessandro Conflitti , Ricardo Mamede

The extended Schur functions form a basis of quasisymmetric functions that contains the Schur functions. We provide a representation-theoretic interpretation of this basis by constructing $0$-Hecke modules whose quasisymmetric…

Representation Theory · Mathematics 2019-06-12 Dominic Searles

We revisit a double-scaled limit of the superconformal index of ${\cal N}=2$ superconformal field theories (SCFTs) which generalizes the Schur index. The resulting partition function, $\hat {\cal Z}(q,\alpha)$, has a standard $q$-expansion…

High Energy Physics - Theory · Physics 2025-07-08 Anirudh Deb , Shlomo S. Razamat

The involution Stanley symmetric functions $\hat{F}_y$ are the stable limits of the analogues of Schubert polynomials for the orbits of the orthogonal group in the flag variety. These symmetric functions are also generating functions for…

Combinatorics · Mathematics 2017-11-10 Zachary Hamaker , Eric Marberg , Brendan Pawlowski

The ring of symmetric functions occupies a central place in algebraic combinatorics, with a particularly notable role in Schubert calculus, where the standard cell decompositions of Grassmannians yield the celebrated family of Schur…

Algebraic Topology · Mathematics 2023-07-20 Oliver Pechenik , Matthew Satriano

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

Some new relations on skew Schur function differences are established both combinatorially using Sch\"utzenberger's jeu de taquin, and algebraically using Jacobi-Trudi determinants. These relations lead to the conclusion that certain…

Combinatorics · Mathematics 2014-01-30 Ronald C. King , Trevor A. Welsh , Stephanie J. van Willigenburg

We define a number of related combinatorial objects, each of which possesses a surprising symmetry. We include several applications such as a combinatorial explanation for certain fixed points of the involution $\omega$ on the ring of…

Combinatorics · Mathematics 2018-09-13 Graham Hawkes

The Schur functions, a basis for the symmetric polynomials (Sym), encode the irreducible representations of the symmetric group, $\mathfrak{S}_n$, via the Frobenius characteristic map. In 1996, Krob and Thibon defined a quasisymmetric…

Combinatorics · Mathematics 2024-05-20 Angela Hicks , Samantha Miller-Brown

Let $\Pi_n$ denote the set of all set partitions of $\{1,2,\ldots,n\}$. We consider two subsets of $\Pi_n$, one connected to rook theory and one associated with symmetric functions in noncommuting variables. Let $\cE_n\sbe\Pi_n$ be the…

Combinatorics · Mathematics 2010-08-18 Mahir Bilen Can , Bruce E. Sagan

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. We then discuss a family of polynomials…

Combinatorics · Mathematics 2013-03-18 Jeffrey Ferreira

We construct a generalization of the theory of symmetric functions involving functions of commuting and anticommuting (Grassmannian) variables. These new functions, called symmetric functions in superspace, are invariant under the diagonal…

Combinatorics · Mathematics 2007-05-23 P. Desrosiers , L. Lapointe , P. Mathieu