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Related papers: Block-Transitive Designs in Affine Spaces

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Given five positive integers $v, m,k,\lambda$ and $t$ where $v \geq k \geq t$ and $v \geq m \geq t,$ a $t$-$(v,k,m,\lambda)$ general covering design is a pair $(X,\mathcal{B})$ where $X$ is a set of $v$ elements (called points) and…

Combinatorics · Mathematics 2012-12-21 Federico Montecalvo

We try to embed a t-design in a finite commutative group in such a way that the sum of the k points of a block is zero. We can compute the number of blocks of the boolean 2-design having all the non zero vectors of $(Z_2)^n$ as the set of…

Combinatorics · Mathematics 2008-07-03 Andrea Caggegi , Alfonso Di Bartolo , Giovanni Falcone

Let PG$(\mathbb{F}_q^v)$ be the $(v-1)$-dimensional projective space over $\mathbb{F}_q$ and let $\Gamma$ be a simple graph of order ${q^k-1\over q-1}$ for some $k$. A 2$-(v,\Gamma,\lambda)$ design over $\mathbb{F}_q$ is a collection $\cal…

Combinatorics · Mathematics 2020-11-30 Marco Buratti , Anamari Nakic , Alfred Wassermann

The affine quantum Schur algebra is a certain important infinite dimensional algebra whose representation theory is closely related to that of quantum affine $\frak{gl}_n$. Finite dimensional irreducible modules for the affine quantum Schur…

Representation Theory · Mathematics 2013-04-23 Qiang Fu

In this article, we study symmetric designs admitting flag-transitive, point-imprimitive almost simple automorphism groups with socle sporadic simple groups. As a corollary, we present a classification of symmetric designs admitting…

Group Theory · Mathematics 2023-07-12 Seyed Hassan Alavi , Ashraf Daneshkhah

We view a design $\mathcal{D}$ as a set of $k$-subsets of a fixed set $X$ of $v$ points. A $k$-subset of $X$ is at distance $i$ from $\mathcal{D}$ if it intersects some $k$-set in $\mathcal{D}$ in $k-i$ points, and no subset in more than…

Combinatorics · Mathematics 2014-05-12 Chris D. Godsil , Cheryl E. Praeger

In this paper, we prove that the minimal number of affine maps on C^n, required to form a hypercyclic abelian semigroup on C^n is n+1. We also prove that the action of any abelian group finitely generated by affine maps on C^n, is never…

Dynamical Systems · Mathematics 2013-09-10 Yahya N'Dao

Recent classification of $\frac{3}{2}$-transitive permutation groups leaves us with six families of groups which are $2$-transitive, or Frobenius, or one-dimensional affine, or the affine solvable subgroups of $ \mathrm{AGL}(2, q)$, or…

Group Theory · Mathematics 2024-02-28 Jiawei He , Xiaogang Li

We prove that the natural permutation representation of highly transitive finite groups cannot be realized as the full automorphism group of an idempotent, finite-dimensional evolution algebra acting on the set of lines spanned by its…

Rings and Algebras · Mathematics 2025-01-14 Cristina Costoya , Pedro Mayorga , Antonio Viruel

We consider how changes in transfinite machine architecture can sometimes alter substantially their capabilities. We approach the subject by answering three open problems touching on: firstly differing halting time considerations for…

Logic · Mathematics 2020-12-16 Philip Welch

A group divisible design $\mbox{GDD}(m,n;\lambda_1,\lambda_2)$, is an ordered pair $(V, \cal{B})$ where $V$ is an $(m+n)$-set of symbols while $\cal{B}$ is a collection of $3$-subsets (called blocks) of $V$ satisfying the following…

Combinatorics · Mathematics 2018-02-27 Chariya Uiyyasathian , Nataphan Kitisin

A design is additive under an abelian group $G$ (briefly, $G$-additive) if, up to isomorphism, its point set is contained in $G$ and the elements of each block sum up to zero. The only known Steiner 2-designs that are $G$-additive for some…

Combinatorics · Mathematics 2022-09-21 Marco Buratti , Anamari Nakić

In this paper, we give a partial solution to a new isomorphism problem about $2$-$(v,k,k-1)$ designs from disjoint difference families in finite fields and Galois rings. Our results are obtained by carefully calculating and bounding some…

Combinatorics · Mathematics 2019-11-21 Christian Kaspers , Alexander Pott

We classify the neighbour-transitive codes in Johnson graphs J(v, k) of minimum distance at least three which admit a neighbour-transitive group of automorphisms that is an almost simple two-transitive group of degree v and does not occur…

Combinatorics · Mathematics 2013-08-05 Max Neunhoeffer , Cheryl E Praeger

We study $t$-designs of parameters $(n,k,\lambda)$ over finite fields as group divisible designs and set systems admitting a transitive action of a linear group encoded in an hypergraph $G$ whose vertex set of size $n$ is partitioned into…

Combinatorics · Mathematics 2018-10-26 Alberto Besana , Cristina Martinez

A design is called $t$-pyramidal when it has an automorphism group which fixes $t$ points and acts sharply transitively on the remaining points. We determine all symmetric $(2^k-1,2^{k-1},2^{k-2})$-designs which are $(2^{k-1}-1)$-pyramidal…

Combinatorics · Mathematics 2025-08-26 Mark Pankov

This paper deals essentially with affine or projective transformations of Lie groups endowed with a flat left invariant affine or projective structure. These groups are called flat affine or flat projective Lie groups. Our main results…

Differential Geometry · Mathematics 2016-02-29 Alberto Medina , Omar Saldarriaga , Hernan Giraldo

In this paper we find all permutations of the level k weights of the affine algebra A_r^{(1)} which commute with both its S and T modular matrices. We find that all of these are simple current automorphisms and their conjugations.…

High Energy Physics - Theory · Physics 2007-05-23 Terry Gannon

This paper studies separating invariants of finite groups acting on affine varieties through automorphisms. Several results, proved by Serre, Dufresne, Kac-Watanabe and Gordeev, and Jeffries and Dufresne exist that relate properties of the…

Commutative Algebra · Mathematics 2017-04-14 Fabian Reimers

A $2$-$(v,k,\lambda)$ design is additive (or strongly additive) if it is possible to embed it in a suitable abelian group $G$ in such a way that its block set is contained in (or coincides with) the set of all the zero-sum $k$-subsets of…

Combinatorics · Mathematics 2023-07-18 Marco Buratti , Anamari Nakic
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