BE-代数上的模与半本原BE-代数

文[1]中引进了BE—代数以后,文[2]给出了这种代数的同态、同构定理,本文在[1]、[2]的基础上,把[5]中带算BCK—代数的概念加以抽象化,引进BE—代数上的模概念以及半本原BE—代数和BE—代数的Jacobson根,讨论这种模的一些基本性质,给出Jacobson根的表达式,证明了半本原BE—代数的结构定理。本文中BE—代数均指M(E):(E,·,1)为么半群。所用符号和术语同[1]、[2]、[3]、[4]。     

一类缺项级数在有理点上值的代数无关性

<正> 文献[1]—[4]考察了一些特殊数组的代数无关性.本文一般地研究了一类缺项级数在某些有理点上值的代数无关性。[1]—[4]中的结果都是本文定理的特例.     

关于代数体函数的一个定理

1965年何育赞在[1],[2]中系统论述了代数体函数的基本值分布性质,并结合导数对第二基本不等式作了若干推广。给出了代数体函数及其导数的一些亏量关系。本文给出了一个定理,应用此定理可以改善[1],[2],[3]中的若干定理。关于 T(r,u)的上界,我们有定理 设 u(z)是代数体函数,a_i(i=1,…,p)是相互判别的有穷复数,b_j(j=1,…,q)是相互判别的有穷非零复数,k≥1为整数。则     

Wlelandt—Hoffman定理的简单证明

文[1]用较长的篇幅给出了Wielandt—Hoffman定理的证明。该定理最早由Hoffman和Wielandt于1953年给出,并基于线性规划的理论绐出了证明(见文[2]),1965年曾由Wilkinson给出纯代数的证明(见文[3]),本文借助双重随机矩阵的一个性质,给出一种相当简单的证明方法。为方便起见,先将原定理叙     

滤过过程及其二个中心极限定理

本文讨论点过程的生成泛函与累积阶乘矩测度,给出了滤过过程的两个重要中心极限定理,改进了[4]、[5]中的有关结果。     

关于泛代数的积的几点注记

<正> 在泛代数理论的研究中,由于直积是由一族已知代数构造新代数的一个重要方法,故对直积的研究一直为许多作者注意(例如,见[1—5]).在我国数学工作者对泛代数的研究中,王世强的[6]是较早的一篇。作者在本文中也要对代数的直积作些讨论,分别对积代数的子代数、同态和合同关系得到一些结果,并指出其某些应用.为了方便起见,我们把代数的直积称为积或积代数;而本文中用到的有关泛代数的概念及结果请参看G.Gratzer的专著[1].     

构造求方程重根高阶迭代公式的基本定理

在[1]中已经介绍了构造高阶多点迭代公式的基本定理:设φ(x)d是p阶的,则φ(x)=φ(x)-f(φ(x))/f′(x)是P 1阶的,[2]中又给出了[1]的一个改进了的基本定理,但这些定理仅适用于方程f(x)是单根的情况.本文针对φ′(x_*)的性质,提出了在重根情况下亦适用的多点迭代构造定理.     

关于离散形式结点域定理证明的几点注记

本文指出了文[1]的主要定理(定理4与定理6)证明中的错误,并对其进行了修正,给出了正确的证明.     

sl(2,F)PBW定理的另一种证明

设F是任意域,L是F上任意一个李代数,文献[1]给出了关于L的PBW定理及证明.本文对L=sl(2,F)我们给出了PBW定理的另一种证明方法.     

集对代数软代数的集对表示

指出文[1]中的软代数表示定理（定理2．2）的错误,给出修改后的软代数表示定理。另外,讨论了集对代数的理想、同余关系和同余理想。     

A new class of unique product monoids with applications to ring theory

We introduce a class of ordered monoids defined by the existence of certain “unique products” with respect to artinian and narrow subsets of the monoid. The logical relationships between this and other significant classes of monoids are explicated with several examples. We conclude with results on skew generalized power series rings. The new class of monoids provides the appropriate setting for obtaining results on reduced rings and domains of skew generalized power series, and on analogues of Armendariz rings.     

Möbius inversion formula for monoids with zero

The Möbius inversion formula, introduced during the 19th century in number theory, was generalized to a wide class of monoids called locally finite such as the free partially commutative, plactic and hypoplactic monoids for instance. In this contribution are developed and used some topological and algebraic notions for monoids with zero, similar to ordinary objects such as the (total) algebra of a monoid, the augmentation ideal or the star operation on proper series. The main concern is to extend the study of the Möbius function to some monoids with zero, i.e., with an absorbing element, in particular the so-called Rees quotients of locally finite monoids. Some relations between the Möbius functions of a monoid and its Rees quotient are also provided.     

Partial symmetry, reflection monoids and Coxeter groups

This is the first of a series of papers in which we initiate and develop the theory of reflection monoids, motivated by the theory of reflection groups. The main results identify a number of important inverse semigroups as reflection monoids, introduce new examples, and determine their orders.     

On the word problem for syntactic monoids of piecewise testable languages

Piecewise testable languages are widely studied area in the theory of automata. We analyze the algebraic properties of these languages via their syntactic monoids. In this paper a normal form is presented for 2- and 3-piecewise testable languages and a log-asymptotic estimate is given for the number of words over these monoids.     

含幺逆半群的半格的同余对

本文利用一族含幺逆半群的同余对刻画了其半格的同余对,并给出了含幺逆半群半格的正规同余对族的格与其标准同余对的格之间的同构关系.     

Eulerian* -polynomial identities on matrix algebras

In this paper we considerably strengthen a result of Ribenboim on noetherian generalised power series rings. While Ribenboim proves his result under the restrictive assumption that the monoid occuring in the definition of the geralised power series ring in cancellative we prove a corresponding result for arbitrary ordered monoids.     

Atomic Commutative Monoids and Their Elasticity

We present some characterizations of properties related to factorization problems on finitely generated commutative monoids. We also give a series of algorithms for studying these problems from a presentation of a given commutative monoid.     

On sofic monoids

We investigate a notion of soficity for monoids. A group is sofic as a group if and only if it is sofic as a monoid. All finite monoids, all commutative monoids, all free monoids, all cancellative one-sided amenable monoids, all multiplicative monoids of matrices over a field, and all monoids obtained by adjoining an identity element to a semigroup are sofic. On the other hand, although the question of the existence of a non-sofic group remains open, we prove that the bicyclic monoid is not sofic. This shows that there exist finitely presented amenable inverse monoids that are non-sofic.     

Constructions and presentations for monoids

Presentations are found for the wreath product of two monoids, the Schützenberger product of two monoids, the Bruck-Reilly extension of a monoid, strong semilattices of monoids and Rees matrix semigroups of monoids.