某些子群是半正规的有限群

本文旨在考查极大子群对有限群结构的影响．首先给出了商群超可解的群是超可解群的若干充分条件；其次考查了ｎ－极大子群对有限群的可解性及超可解性的影响     

某些子群介于正规与反正规之间的有限群北大核心CSCD

有限群G的子群H称为G的BNA子群,若对任意的x∈G有H^(x)=H或x∈.若有限群G的所有素数阶和4阶循环子群都是G的BNA子群,则称G为CBNA群.本文主要刻画CBNA群的结构,并且给出所有真子群都是CBNA群的完全分类.     

某些C-正规子群对有限群结构的影响

利用某些子群的C正规性,得到有限群成为可解的一系列充分条件     

具有极大循环子群的P-群的模糊子群构造北大核心

依据模糊子群与子群列之间的关系,通过分析具有极大循环子群的P-群的子群列的构造特点,给出了能够反映具有极大循环子群的P-群的模糊子群构造特征的模糊子群的阶、极大模糊子群和模糊子群的等价类数的计算公式.     

子群次正规性对有限群可解性的影响

考查了次正规子群对有限群结构的影响,得到有限群可解的若干充分条件和超可解的一个充分条件.     

有限群的s-条件置换子群

如果对群G的任意Sylow子群T,存在一个元素x∈G,使得HTx=TxH,那么称群G的子群H在G中s-条件置换.利用s-条件置换子群给出了一些群的性质和结构.     

有限群的s-条件置换子群

如果对群G的任意Sylow子群T,存在一个元素x∈G,使得HT~x=T~xH,那么称群G的子群H在G中s-条件置换．利用s-条件置换子群给出了一些群的性质和结构．     

某些幂零子群与可解性

本文利用某些幂子群的半正规性,讨论有限群的可解性,所得结果统一推广了王品超、赵耀庆的若干结果。     

Weyl群的子群结构

对各种类型的不可约根系,讨论了其Ｗｅｙｌ群一类子群的极大性。     

六阶图G与Sn的积图的交叉数

确定图的交叉数是NP．完全问题．目前已确定交叉数的六阶图与星图的笛卡尔积图极少。本文确定了—个六阶图G与星图5k积图的交叉数为Z（6,n）＋2n＋[n/2].     

Finite p-Groups All of Whose Proper Quotient Groups are Abelian or Inner-Abelian

In this article, finite p-groups all of whose proper quotient groups are abelian or inner-abelian are classified. As a corollary, finite p-group all of whose proper quotient groups are abelian, and finite p-groups all of whose proper sections are abelian or inner-abelian are also classified.     

Finite p-Groups in Which the Number of Subgroups of Possible Order is Less Than or Equal to $p^3 $

In this paper, groups of order pn in which the number of subgroups of possible order is less than or equal to p3 are classified. It turns out that if p 2, n ≥ 5, then the classification of groups of order pn in which the number of subgroups of possible order is less than or equal to p3 and the classification of groups of order pn with a cyclic subgroup of index p2 are the same.     

Finite p-Groups all of Whose Maximal Subgroups Either are Metacyclic or Have a Derived Subgroup of Order ≤ p

The groups as mentioned in the title are classified up to isomorphism. This is an answer to a question proposed by Berkovich and Janko.     

On G-Covering Subgroup Systems for Some Saturated Formations of Finite Groups

Let ? be a class of groups and G a finite group. We call a set Σ of subgroups of G a G-covering subgroup system for ? if G ∈ ? whenever Σ ? ?. For a non-identity subgroup H of G, we put Σ _H be some set of subgroups of G which contains at least one supplement in G of each maximal subgroup of H. Let p ≠ q be primes dividing |G|, P, and Q be non-identity a p-subgroup and a q-subgroup of G, respectively. We prove that Σ _P and Σ _P  ∪ Σ _Q are G-covering subgroup systems for many classes of finite groups.     

一些特殊的p核p群

给出了一些特殊的p核p群的分类,并给出了一些非正则p核p群的例子.     

Finite p-groups All of Whose Minimal Nonabelian Subgroups are Nonmetacyclic of Order p3

Assume p is an odd prime. We investigate finite p-groups all of whose minimal nonabelian subgroups are of order p³. Let P₁-groups denote the p-groups all of whose minimal nonabelian subgroups are nonmetacyclic of order p³. In this paper, the P₁-groups are classified, and as a by-product, we prove the Hughes' conjecture is true for the P₁-groups.     

关于有限p-群的正规闭包的一些条件

Berkovich 提出了研究满足下列条件的有限p-群G, 对于G的每一个非正规子群H满足(N₁)exp(H)=exp(H^G); (N₂) |H^G:H|≤ p; (N₃) H^G=HG''. 本文首先研究满足条件(N₃) 的有限p-群,然后讨论满足条件(N₁); (N₂) 和(N₃) 的有限p-群.     

有限超特殊p-群的一个注记

本文获得了以下结果：设G为有限超特殊P-群．则下列条件等价：（1）G的非平凡特征子群的阶相同;（2）G的非平凡特征子群唯一;（3）当p〉2时,exp G=p;当P=2时,G≠D8．     

Finite <Emphasis Type="Italic">p</Emphasis>-groups with a class of complemented normal subgroups

Assume G is a finite group and H a subgroup of G. If there exists a subgroup K of G such that G = HK and H ∩ K = 1, then K is said to be a complement to H in G. A finite p-group G is called an NC-group if all its proper normal subgroups not contained in Φ(G) have complements. In this paper, some properties of NC-groups are investigated and some classes of NC-groups are classified.