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Related papers: Exploring a Delta Schur Conjecture

200 papers

In The Delta Conjecture (arxiv:1509.07058), Haglund, Remmel and Wilson introduced a four variable $q,t,z,w$ Catalan polynomial, so named because the specialization of this polynomial at the values $(q,t,z,w) = (1,1,0,0)$ is equal to the…

Combinatorics · Mathematics 2018-10-10 Mike Zabrocki

Fix an integer $t \geq 2$ and a primitive $t^{\text{th}}$ root of unity $\omega$. We consider the specialized skew hook Schur polynomial $\text{hs}_{\lambda/\mu}(X,\omega X,\dots,\omega^{t-1}X/Y,\omega Y,\dots,\omega^{t-1}Y)$, where…

Combinatorics · Mathematics 2025-12-19 Nishu Kumari

We prove a positive combinatorial formula for the Schur expansion of LLT polynomials indexed by a 3-tuple of skew shapes. This verifies a conjecture of Haglund. The proof requires expressing a noncommutative Schur function as a positive sum…

Combinatorics · Mathematics 2014-11-14 Jonah Blasiak

We make a systematic study of a new combinatorial construction called a dual equivalence graph. We axiomatize these graphs and prove that their generating functions are symmetric and Schur positive. By constructing a graph on ribbon…

Combinatorics · Mathematics 2013-10-24 Sami H. Assaf

We introduce a variety $Y_{n,k}$, which we call the \textit{affine $\Delta$-Springer fiber}, generalizing the affine Springer fiber studied by Hikita, whose Borel-Moore homology has an $S_n$ action and a bigrading that corresponds to the…

Combinatorics · Mathematics 2025-01-03 Maria Gillespie , Eugene Gorsky , Sean T. Griffin

In 10.1093/imrn/rnac258, the authors conjecture a combinatorial formula for the expressions $\Xi e_\alpha \rvert_{t=1}$, known as Symmetric Theta Trees Conjecture, in terms of tiered trees with an inversion statistic. In…

Combinatorics · Mathematics 2024-07-03 Alessandra Caraceni , Alessandro Iraci

Inspired by [Qiu, Wilson 2019] and [D'Adderio, Iraci, Vanden Wyngaerd 2019 - Delta Square], we formulate a generalised Delta square conjecture (valley version). Furthermore, we use similar techniques as in [Haglund, Sergel 2019] to obtain a…

Combinatorics · Mathematics 2022-06-27 Alessandro Iraci , Anna Vanden Wyngaerd

Egge, Loehr and Warrington gave in \cite{ELW} a combinatorial formula that permits to convert the expansion of a symmetric function, homogeneous of degree $n$, in terms of Gessel's fundamental quasisymmetric functions into an expansion in…

Combinatorics · Mathematics 2018-02-28 Adriano Garsia , Jeffrey Remmel

In a 2016 ArXiv posting F. Bergeron listed a variety of symmetric functions $G[X;q]$ with the property that $G[X;1+q]$ is $e$-positive. A large subvariety of his examples could be explained by the conjecture that the Dyck path LLT…

Combinatorics · Mathematics 2019-04-18 Adriano M. Garsia , James Haglund , Dun Qiu , Marino Romero

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 introduce the new combinatorial approach of plethystic type of tableaux, as a method to understand coefficients of Schur functions appearing in plethysms $s_\nu[h_\lambda]$ and $s_{\nu}[e_{\lambda}]$, for any partitions $\lambda$ and…

Combinatorics · Mathematics 2022-09-30 Florence Maas-Gariépy , Étienne Tétreault

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 make a systematic study of a new combinatorial construction called a dual equivalence graph. We axiomatize these graphs and prove that their generating functions are symmetric and Schur positive. This provides a universal method for…

Combinatorics · Mathematics 2020-03-05 Sami H. Assaf

In the context of the (generalized) Delta Conjecture and its compositional form, D'Adderio, Iraci, and Wyngaerd recently stated a conjecture relating two symmetric function operators, $D_k$ and $\Theta_k$. We prove this Theta Operator…

Combinatorics · Mathematics 2020-04-14 Marino Romero

Our main result here is that the specialization at $t=1/q$ of the $Q_{km,kn}$ operators studied in [4] may be given a very simple plethystic form. This discovery yields elementary and direct derivations of several identities relating these…

Combinatorics · Mathematics 2015-01-06 A. M. Garsia , E. Leven , N. Wallach , G. Xin

In this article, we will prove the Giambelli formula for Schur multiple zeta-functions of extended shape which we call laced type, using the combinatorial method of proving the Giambelli formula for Schur function by Egecioglu and Remmel.…

Number Theory · Mathematics 2025-09-19 Kohji Matsumoto , Maki Nakasuji

Haglund, Luoto, Mason, and van Willigenburg introduced a basis for quasisymmetric functions called the quasisymmetric Schur function basis, generated combinatorially through fillings of composition diagrams in much the same way as Schur…

Combinatorics · Mathematics 2011-10-19 Sarah Mason , Jeffrey Remmel

In this paper, we formulate a rational analog of the fall Delta theorem and the Delta square conjecture. We find a new dinv statistic on fall-decorated paths on a $(m+k) \times (n+k)$ rectangle that simultaneously extends the previously…

Combinatorics · Mathematics 2025-08-29 Alessandro Iraci , Roberto Pagaria , Giovanni Paolini

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

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