Semigroup Forum最新文献_第5页

The isomorphism problem for ideal class monoids of numerical semigroups 数值半群理想类单体的同构问题

IF 0.7 3区数学

Semigroup Forum Pub Date : 2024-04-16 DOI: 10.1007/s00233-024-10429-7

P. A. García-Sánchez

引用次数: 0

Lattice isomorphisms of orthodox semigroups with no nontrivial finite subgroups 无非重要有限子群的正统半群的晶格同构

IF 0.7 3区数学

Semigroup Forum Pub Date : 2024-04-16 DOI: 10.1007/s00233-024-10428-8

Simon M. Goberstein

引用次数: 0

Topological sensitivity for semiflow 半流拓扑敏感性

IF 0.7 3区数学

Semigroup Forum Pub Date : 2024-04-16 DOI: 10.1007/s00233-024-10425-x

Ali Barzanouni, Somayyeh Jangjooye Shaldehi

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引用次数: 0

Atomic density of arithmetical congruence monoids 算术全等单体的原子密度

IF 0.7 3区数学

Semigroup Forum Pub Date : 2024-04-12 DOI: 10.1007/s00233-024-10426-w

Nils Olsson, Christopher O’Neill, Derek Rawling

引用次数: 0

The André–Quillen cohomology of commutative monoids 交换单元的安德烈-奎伦同调

IF 0.7 3区数学

Semigroup Forum Pub Date : 2024-04-09 DOI: 10.1007/s00233-024-10423-z

Bhavya Agrawalla, Nasief Khlaif, Haynes Miller

引用次数: 0

Finite semigroups and periodic sums systems in $$beta mathbb {N}$$ and their Ramsey theoretic consequences $$beta mathbb {N}$ 中的有限半群和周期和系统及其拉姆齐理论后果

IF 0.7 3区数学

Semigroup Forum Pub Date : 2024-04-05 DOI: 10.1007/s00233-024-10424-y

Yevhen Zelenyuk

{"title":"Finite semigroups and periodic sums systems in $$beta mathbb {N}$$ and their Ramsey theoretic consequences","authors":"Yevhen Zelenyuk","doi":"10.1007/s00233-024-10424-y","DOIUrl":"https://doi.org/10.1007/s00233-024-10424-y","url":null,"abstract":"Let (m,nge 2) and define (nu :omega rightarrow {0,ldots ,m-1}) by (nu (k)equiv kpmod {m}). We construct some new finite semigroups in (beta mathbb {N}), in particular, a semigroup generated by m elements of order n with cardinality (m^n+m^{n-1}+cdots +m). We also show that, for (nge m), there is a sequence (p_0,ldots ,p_{m-1}) in (beta mathbb {N}) such that all sums (sum _{j=i}^{i+k}p_{nu (j)}), where (iin {0,ldots ,m-1}) and (kin {0,ldots ,n-1}), are distinct and (sum _{j=i}^{i+n}p_{nu (j)}=sum _{j=i}^{i+n-m}p_{nu (j)}) for each i. As consequences we derive some new Ramsey theoretic results. In particular, we show that, for (nge m), there is a partition ({A_{i,k}:(i,k)in {0,ldots ,m-1}times {0,ldots ,n-1}}) of (mathbb {N}) such that, whenever for each (i, k), (mathscr {B}_{i,k}) is a finite partition of (A_{i,k}), there exist (B_{i,k}in mathscr {B}_{i,k}) and a sequence ((x_j)_{j=0}^infty ) such that for every finite sequence (j_0<ldots <j_s) such that (j_{t+1}equiv j_t+1pmod {m}) for each (t<s), one has (x_{j_0}+cdots +x_{j_s}in B_{i_0,k_0}), where (i_0=nu (j_0)) and (k_0) is s if (sle n-1) and (n-m+nu (s-n)) otherwise.","PeriodicalId":49549,"journal":{"name":"Semigroup Forum","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140577923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Set-theoretical solutions of the pentagon equation on Clifford semigroups 克利福德半群上五边形方程的集合论解

IF 0.7 3区数学

Semigroup Forum Pub Date : 2024-03-27 DOI: 10.1007/s00233-024-10421-1

Marzia Mazzotta, Vicent Pérez-Calabuig, Paola Stefanelli

引用次数: 0

The natural partial order on semigroups of transformations with restricted range that preserve an equivalence 保留等价性的限定范围变换半群上的自然偏序

IF 0.7 3区数学

Semigroup Forum Pub Date : 2024-03-27 DOI: 10.1007/s00233-024-10422-0

Kritsada Sangkhanan, Jintana Sanwong

引用次数: 0

Exponential stability of extensible beams equation with Balakrishnan–Taylor, strong and localized nonlinear damping 具有 Balakrishnan-Taylor、强和局部非线性阻尼的可扩展梁方程的指数稳定性