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In this paper, we give some results concerning atomic decompositions for operators on reproducing kernel Hilbert spaces, using frame theory techniques. We provide also generalizations for atomic decompositions of some theorems for…

Functional Analysis · Mathematics 2014-02-03 Laura Gavruta

We obtain a new family of relations satisfied by the partition function. In contrast with most partition relations, these involve non-trivial roots of unity. We present two proofs, one using the fact that the discriminant modular form is a…

Number Theory · Mathematics 2025-09-29 Florian Breuer , Fabien Pazuki

We provide new formulas for the coefficients in the partial fraction decomposition of the restricted partition generating function. These techniques allow us to partially resolve a recent conjecture of Sills and Zeilberger. We also describe…

Number Theory · Mathematics 2014-01-14 Cormac O'Sullivan

For each composition $\vec{c}$ we show that the order complex of the poset of pointed set partitions $\Pi^{\bullet}_{\vec{c}}$ is a wedge of spheres of the same dimension with the multiplicity given by the number of permutations with…

Combinatorics · Mathematics 2013-12-10 Richard Ehrenborg , JiYoon Jung

Consider a coring with exact rational functor, and a finitely generated and projective right comodule. We construct a functor (\emph{coinduction functor}) which is right adjoint to the hom-functor represented by this comodule. Using the…

Rings and Algebras · Mathematics 2009-02-13 L. El Kaoutit , J. Gómez-Torrecillas

We address the conjectures left by the recent article by Ferreira et al. titled ``Commuting maps and identities with inverses on alternative division rings.'' We also present an example showing the necessity of the conditions of the results…

Rings and Algebras · Mathematics 2024-03-28 Daniel Kawai , Bruno Leonardo Macedo Ferreira

The paper contains an exposition of part of topology using partitions of unity. The main idea is to create variants of the Tietze Extension Theorem and use them to derive classical theorems. This idea leads to a new result generalizing…

General Topology · Mathematics 2008-02-28 Jerzy Dydak

In this short note we show that representation and character varieties of discrete groups can be viewed as tensor products of suitable functors over the PROP of cocommutative Hopf algebras. Such view point has several interesting…

Rings and Algebras · Mathematics 2016-10-11 Martin Kassabov , Sasha Patotski

We study the behaviour of infinitesimal deformation functors of local group actions with regard to passing to subgroups and quotient groups. Inspired by the cohomological information, we conjecture the existence of a decomposition of a…

Algebraic Geometry · Mathematics 2011-12-05 Jakub Byszewski

We introduce heavily separable functors of the second kind and study them in three different situations. The first of these is with restrictions and extensions of scalars for modules over small preadditive categories. The second is with…

Rings and Algebras · Mathematics 2023-06-30 Abhishek Banerjee , Subhajit Das

We develop a functorial approach to the study of the homotopy groups of spheres and Moore spaces $M(A,n)$, based on the Curtis spectral sequence and the decomposition of Lie functors as iterates of simpler functors such as the symmetric or…

Algebraic Topology · Mathematics 2014-10-01 Lawrence Breen , Roman Mikhailov

It is well-known that tensor decompositions show separations, that is, that constraints on local terms (such as positivity) may entail an arbitrarily high cost in their representation. Here we show that many of these separations disappear…

Optimization and Control · Mathematics 2021-09-03 Gemma De las Cuevas , Andreas Klingler , Tim Netzer

We generalize Bouc's construction of orthogonal idempotents in the double Burnside algebra to the setting of the double $\mathbb{C}^\times$-fibered Burnside algebra. This yields a structural decomposition of the evaluations of…

Representation Theory · Mathematics 2026-05-04 Olcay Coşkun , Ruslan Muslumov

This paper surveys, and in some cases generalises, many of the recent results on homomorphisms and the higher Ext groups for q-Schur algebras and for the Hecke algebra of type A. We review various results giving isomorphisms between Ext…

Representation Theory · Mathematics 2007-05-23 Anton Cox , Alison Parker

Via a functor from certain Lorentzian to Riemannian manifolds, we obtain a finiteness result.

Differential Geometry · Mathematics 2022-08-23 Olaf Müller

We construct explicit global homotopies for differential Hochschild cochains in differential geometry, thereby upgrading the classical Hochschild-Kostant-Rosenberg map to a deformation retract. Our approach combines two key techniques: a…

Differential Geometry · Mathematics 2026-05-01 Marvin Dippell , Chiara Esposito , Jonas Schnitzer , Stefan Waldmann

The homology of free Lie algebras with coefficients in tensor products of the adjoint representation working over Q contains important information on the homological properties of polynomial outer functors on free groups. The latter…

Algebraic Topology · Mathematics 2025-12-17 Geoffrey Powell

Decomposition systems with rapidly decaying elements (needlets) based on Hermite functions are introduced and explored. It is proved that the Triebel-Lizorkin and Besov spaces on $\R^d$ induced by Hermite expansions can be characterized in…

Classical Analysis and ODEs · Mathematics 2007-05-23 Pencho Petrushev , Yuan Xu

We prove descent theorems for semiorthogonal decompositions using techniques from derived algebraic geometry. Our methods allow us to capture more general filtrations of derived categories and even marked filtrations, where one descends not…

Algebraic Geometry · Mathematics 2021-01-12 Benjamin Antieau , Elden Elmanto

We show a general scheme of Ramsey-type results for partitions of countable sets of finite functions, where "one piece is big" is interpreted in the language originating in creature forcing. The heart of our proofs follows Glazer's proof of…

Logic · Mathematics 2015-03-17 Andrzej Roslanowski , Saharon Shelah