Results 41 to 50 of about 56,755 (205)
Colourings of Uniform Group Divisible Designs and Maximum Packings
Journal of Combinatorial Designs, EarlyView.ABSTRACT A weak c $c$‐colouring of a design is an assignment of colours to its points from a set of c $c$ available colours, such that there are no monochromatic blocks. A colouring of a design is block‐equitable, if for each block, the number of points coloured with any available pair of colours differ by at most one.
Andrea C. Burgess +6 more
wiley +1 more source
An inverse Grassmannian Littlewood–Richardson rule and extensions
Forum of Mathematics, SigmaChow rings of flag varieties have bases of Schubert cycles $\sigma _u $ , indexed by permutations. A major problem of algebraic combinatorics is to give a positive combinatorial formula for the structure constants of this basis.
Oliver Pechenik, Anna Weigandt
doaj +1 more source
Asymptotics of lattice walks via analytic combinatorics in several variables [PDF]
Discrete Mathematics & Theoretical Computer Science, 2020 We consider the enumeration of walks on the two-dimensional non-negative integer lattice with steps defined by a finite set S ⊆ {±1, 0}2 . Up to isomorphism there are 79 unique two-dimensional models to consider, and previous work in this area has used ...
Stephen Melczer, Mark C. Wilson
doaj +1 more source
Representations of reductive normal algebraic monoids
, 2014 The rational representation theory of a reductive normal algebraic monoid (with one-dimensional center) forms a highest weight category, in the sense of Cline, Parshall, and Scott.
D.J. Grigor’ev +7 more
core +1 more source
Journal of Combinatorial Designs, EarlyView.ABSTRACT Capsets are subsets of F 3 n ${{\mathbb{F}}}_{3}^{n}$ with no three points on a line, and a capset is complete if it is not a subset of a larger capset. We study some new constructions of capsets via algebraic equations over extensions of F 3 ${{\mathbb{F}}}_{3}$.
Cassie Grace, José Felipe Voloch
wiley +1 more source
Operads in algebraic combinatorics
CoRR, 2017 The main ideas developed in this habilitation thesis consist in endowing combinatorial objects (words, permutations, trees, Young tableaux, etc.) with operations in order to construct algebraic structures. This process allows, by studying algebraically the structures thus obtained (changes of bases, generating sets, presentations, morphisms ...
openaire +2 more sources
Lattice structure of Grassmann-Tamari orders [PDF]
Discrete Mathematics & Theoretical Computer Science, 2015 The Tamari order is a central object in algebraic combinatorics and many other areas. Defined as the transitive closure of an associativity law, the Tamari order possesses a surprisingly rich structure: it is a congruence-uniform lattice.
Thomas McConville
doaj +1 more source
Enumeration of three term arithmetic progressions in fixed density sets [PDF]
, 2014 Additive combinatorics is built around the famous theorem by Szemer\'edi which asserts existence of arithmetic progressions of any length among the integers. There exist several different proofs of the theorem based on very different techniques.
Sjöland, Erik
core
Spherical nilpotent orbits and abelian subalgebras in isotropy representations [PDF]
, 2016 Let $G$ be a simply connected semisimple algebraic group with Lie algebra $\mathfrak g$, let $G_0 \subset G$ be the symmetric subgroup defined by an algebraic involution $\sigma$ and let $\mathfrak g_1 \subset \mathfrak g$ be the isotropy representation ...
Frajria, Pierluigi Moseneder +2 more
core +3 more sources
Renormalization techniques for inflation systems and some of their applications
Acta Crystallographica Section A, EarlyView.In this work, renormalization methods for quantities related to the diffraction of inflation systems are surveyed.Exact renormalization techniques are important and powerful, particularly for inflation‐generated systems. We review recent results in this direction.
Michael Baake +4 more
wiley +1 more source