具有唯一定长路的有向图的一个注记

Ｌａｍ和ｖａｎ Ｌｉｎｔ构造了一类具有唯一定长路的有向图Ｄ（ｃ，ｋ），其阶为ｎ＝ｃ＾ｋ＋１，并证明Ｄ（ｃ，ｋ）的自同群包含一个２（ｃ＋１）阶二面体群，其中ｃ为大于１的整数，ｋ为大于１的奇数。本文利用（０，１）矩阵方程的性质证明，对任意的整数ｃ＞１和奇数ｋ＞１，存在ψ（ｋ）（ψ为Ｅｕｌｅｒ函数）个ｎ＝Ｃ＾ｋ＋１阶具有唯一定长路的有路的有向图；它们互不同构且其中每一个图的全自同构群都是２（Ｃ＋１）阶二     

一类具有唯一定长路的有向图的自同构群

Ｌａｍ和Ｖａｎ Ｌｉｎｔ 在推广友谊定理时构造了一类具有唯一定长路的有向图（这里 用Ｄ（ｃ，ｋ）表示），并证明了Ｄ（ｃ，ｋ）的自同构群包含一个２（ｃ＋１）阶二面体群。 木文利用Ｄ（ｃ．ｋ）的邻接矩阵的性质证明这个二面体群就是Ｄ（ｃ，ｋ）的全自同构群， 从而解决了 Ｌａｍ和 Ｖａｎ Ｌｉｎｔ作中遗留的问题。     

Polynomial factorization over

We describe algorithms for polynomial factorization over the binary field , and their implementation. They allow polynomials of degree up to to be factored in about one day of CPU time, distributing the work on two processors.

     

Visualization of Effect Algebras by Automorphisms

We show that every effect algebra satisfying the Riesz decomposition property can be represented as an effect algebra of automorphisms of an antilattice, and every MV-algebra can be represented as an MV-algebra of automorphisms of a linearly ordered set. Such a representation enables us to visualize effect algebras by functions. This is a variation of the Holland representation theorem for -groups and of its generalization of Glass for directed interpolation po-groups as -groups or po-groups automorphisms of linearly ordered set or of an antilattice, respectively.     

Automorphism Groups of Computably Enumerable Predicates

We study automorphism groups of two important predicates in computability theory: the predicate W_y and the graph of a universal partially computable function. It is shown that all automorphisms of the predicates in question are computable. The actions of the automorphism groups on some index sets are examined, and we establish a number of results on the structure of these. We also look into homomorphisms of the two predicates. In this case the situation changes: all homomorphisms of the universal function are computable, but in each Turing degree, homomorphisms of W_y exist.     

Commutativity of rings with polynomial constraints

Let p, q and r be fixed non-negative integers. In this note, it is shown that if R is left (right) s-unital ring satisfying , respectively) where , then R is commutative. Moreover, commutativity of R is also obtained under different sets of constraints on integral exponents. Also, we provide some counterexamples which show that the hypotheses are not altogether superfluous. Thus, many well-known commutativity theorems become corollaries of our results.     

|A(G)|=24P2(P为奇素数)的有限Abel群G

利用有限Abel群G的自同构群A(G)的阶来刻划群G的构造,用一种巧妙的方法,推导出了|A(G)|=24P2(P为奇素数)的有限Abel群G的全部类型,并给出了详细的推导.     

第四类华罗庚域上的Bergman核函数

显式给出了第四类华罗庚域HEⅣ上的Bergman核函数及其全纯自同构群。     

对正规子群有极小条件的可解AT群

给出了对正规子群有极小条件的可解AT群的基本结构,推广了有限可解群的Gaschiitz-Schenkman-Carter分解定理.