activity
19972026
most citedCombinatorial Hopf algebras and generalized Dehn-Sommerville relations

133 citations · 1.4k across the 77 of their papers we have counts for

collaborators

79 papers

math.CO2026

Finite noncommutative coinvariant algebras

Farid Aliniaeifard, Nantel Bergeron, Huilan Li +1

We study quotients of free associative algebras by the two-sided ideals generated by positive-degree symmetric, quasisymmetric, or free quasisymmetric polynomials. Free quasisymmet…

math.HO2026

A memorial tribute: Adriano Garsia (1928--2024)

Hélène Barcelo, François Bergeron, Nantel Bergeron +15

Adriano Mario Garsia was born in Tunis on August 20, 1928, to a Tunisian-Italian family. He lived on a farm there until the end of World War II, then moved to Rome. After finishing…

math.CO2026

A Hopf algebra on permutations with a coupling product

Huilan Li, Yishuo Yang, Nantel Bergeron

We define a coupling product and a draw coproduct on permutations and show that they define a graded, connected, cocommutative, free Hopf algebra . In characteristic z…

math.AG2026

The Quasisymmetric Grassmannian

Nantel Bergeron, Lucas Gagnon, Hunter Spink +1

We construct a complex of toric varieties we call the quasisymmetric Grassmannian inside the Grassmannian of -planes in . Each irreducible component is a positroid…

math.AG2026

The Coxeter Flag Variety

Nantel Bergeron, Lucas Gagnon, Hunter Spink +1

For a Coxeter element in a Weyl group , we define the -Coxeter flag variety as the union of left-translated Richardson varieties $w^{-1}…

math.AG2025

The quasisymmetric flag variety: a toric complex on noncrossing partitions

Nantel Bergeron, Lucas Gagnon, Philippe Nadeau +2

We develop the geometric theory of equivariant quasisymmetry via a new ``quasisymmetric flag variety''. This is a toric complex in the flag variety whose fixed point set is the set…

math.CO2025

Equivariant quasisymmetry and noncrossing partitions

Nantel Bergeron, Lucas Gagnon, Philippe Nadeau +2

We introduce a definition of ``equivariant quasisymmetry'' for polynomials in two sets of variables. Using this definition we define quasisymmetric generalizations of the theory of…

math.CO2024

Interval hypergraphic lattices

Nantel Bergeron, Vincent Pilaud

For a hypergraph on , the hypergraphic poset is the transitive closure of the oriented skeleton of the hypergraphic polytope …

math.CO2024

A quantum Murnaghan--Nakayama rule for the flag manifold

Carolina Benedetti, Nantel Bergeron, Laura Colmenarejo +2

In this paper, we give a rule for the multiplication of a Schubert class by a tautological class in the (small) quantum cohomology ring of the flag manifold. As an intermediate ste…

math.CO2023★ 1 cited

Lattices of acyclic pipe dreams

Nantel Bergeron, Noémie Cartier, Cesar Ceballos +1

We show that for any permutation , the increasing flip graph on acyclic pipe dreams with exiting permutation is a lattice quotient of the interval of the weak order.…

math.CO2023

The excedance quotient of the Bruhat order, Quasisymmetric Varieties and Temperley-Lieb algebras

Nantel Bergeron, Lucas Gagnon

Let be the ring of polynomial in variables and consider the ideal generated by quasisym…

math.CO2022

Quasisymmetric harmonics of the exterior algebra

Nantel Bergeron, Kelvin Chan, Farhad Soltani +1

We study the ring of quasisymmetric polynomials in anticommuting (fermionic) variables. Let denote the polynomials in anticommuting variables. The main results of thi…

math.CO2022

{T}he Gröbner Basis of a Catalan Path Ideal

Nantel Bergeron, Xavier Mootoo, Vedarth Vyas

For the ideal in with char() = 0, we show that the reduced Gröbner basi…

math.CO2021

Hopf algebras of parking functions and decorated planar trees

Nantel Bergeron, Rafael S. González D'León, Shu Xiao Li +2

We construct three new combinatorial Hopf algebras based on the Loday-Ronco operations on planar binary trees. The first and second algebras are defined on planar trees and labeled…

math.CO2020

Sign variation and descents

Nantel Bergeron, Aram Dermenjian, John Machacek

For any and , let be the poset of projective equivalence classes of -vectors of length with sign variation bounded by , ordered by…

math.CO2019★ 4 cited

Elliptic and -Analogs of the Fibonomial Numbers

Nantel Bergeron, Cesar Ceballos, Josef Küstner

In 2009, Sagan and Savage introduced a combinatorial model for the Fibonomial numbers, integer numbers that are obtained from the binomial coefficients by replacing each term by it…

math.CO2019★ 10 cited

New Invariants for Permutations, Orders and Graphs

Jean-christophe Aval, Nantel Bergeron, John Machacek

We study the symmetric function and polynomial combinatorial invariants of Hopf algebras of permutations, posets and graphs. We investigate their properties and the relations among…

math.CO2019★ 5 cited

Flagged -partitions

Sami Assaf, Nantel Bergeron

We introduce the theory of -partitions, depending on a poset and a map from to positive integers. The generating function $\mathfra…

math.CO2018★ 12 cited

Hopf dreams and diagonal harmonics

Nantel Bergeron, Cesar Ceballos, Vincent Pilaud

This paper introduces a Hopf algebra structure on a family of reduced pipe dreams. We show that this Hopf algebra is free and cofree, and construct a surjection onto a commutative…

math.CO2018

Stable set polytopes and their 1-skeleta

Farid Aliniaeifard, Carolina Benedetti, Nantel Bergeron +2

We characterize the edges of two classes of -polytopes. The first class corresponds to the stable set polytope of a graph and includes chain polytopes of posets, some inst…

math.CO2017★ 16 cited

Hypergraphic polytopes: combinatorial properties and antipode

Carolina Benedetti, Nantel Bergeron, John Machacek

In an earlier paper, the first two authors defined orientations on hypergraphs. Using this definition we provide an explicit bijection between acyclic orientations in hypergraphs a…

math.CO2016★ 5 cited

Cancelation free formula for the antipode of linearized Hopf monoid

Nantel Bergeron, Carolina Benedetti

Many combinatorial Hopf algebras in the literature are the functorial image of a linearized Hopf monoid . That is, or $H=\overline{\mathcal K}…

math.CO2015★ 42 cited

A Hopf algebra of subword complexes

Nantel Bergeron, Cesar Ceballos

We introduce a Hopf algebra structure of subword complexes, including both finite and infinite types. We present an explicit cancellation free formula for the antipode using acycli…

math.CO2014★ 3 cited

A combinatorial proof that Schubert vs. Schur coefficients are nonnegative

Sami Assaf, Nantel Bergeron, Frank Sottile

We give a combinatorial proof that the product of a Schubert polynomial by a Schur polynomial is a nonnegative sum of Schubert polynomials. Our proof uses Assaf's theory of dual eq…