Generating Series of Key Polynomials and Bounded Ascending Sequences of Integers

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Cape, Noah, Zemel, Shaul
Format: Preprint
Veröffentlicht: 2024
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866915017690972160
author Cape, Noah
Zemel, Shaul
author_facet Cape, Noah
Zemel, Shaul
contents The fact that Schubert polynomials are the weighted counting functions for reduced RC-graphs, also known as reduced pipe dreams, was established using their generating functions inside an appropriate Demazure algebra. Here we investigate the generating functions of another family of polynomials, the key polynomials, also known as Demazure characters. Each component in that function is a rational function, whose denominator is an explicit product whose definition is based on bounded ascending sequences of integers. We determine the first terms of the polynomial numerator, and pose conjectures about these terms in general as well as some of the next ones. The form of our generating functions suggests relations between the coefficients in key polynomials and signed sums of numbers of integral points on polytopes.
format Preprint
id arxiv_https___arxiv_org_abs_2411_08465
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Generating Series of Key Polynomials and Bounded Ascending Sequences of Integers
Cape, Noah
Zemel, Shaul
Combinatorics
05A15, 05A19, 05E99, 05E05
The fact that Schubert polynomials are the weighted counting functions for reduced RC-graphs, also known as reduced pipe dreams, was established using their generating functions inside an appropriate Demazure algebra. Here we investigate the generating functions of another family of polynomials, the key polynomials, also known as Demazure characters. Each component in that function is a rational function, whose denominator is an explicit product whose definition is based on bounded ascending sequences of integers. We determine the first terms of the polynomial numerator, and pose conjectures about these terms in general as well as some of the next ones. The form of our generating functions suggests relations between the coefficients in key polynomials and signed sums of numbers of integral points on polytopes.
title Generating Series of Key Polynomials and Bounded Ascending Sequences of Integers
topic Combinatorics
05A15, 05A19, 05E99, 05E05
url https://arxiv.org/abs/2411.08465