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91.
This is a continuation of the determination begun in K-Theory 10 (1996), 517–596, of explicit index reduction formulas for function fields of twisted flag varieties of adjoint semisimple algebraic groups. We give index reduction formulas for the varieties associated to the classical simple groups of outer type A
n-1 and D
n, and the exceptional simple groups of type E
6 and E
7. We also give formulas for the varieties associated to transfers and direct products of algebraic groups. This allows one to compute recursively the index reduction formulas for the twisted flag varieties of any semi-simple algebraic group. 相似文献
92.
93.
Yu Chen 《Transactions of the American Mathematical Society》1996,348(2):521-541
It is shown that every automorphism of an adjoint Chevalley group over an integral domain containing the rational number field is uniquely expressible as the product of a ring automorphism, a graph automorphism and an inner automorphism while every isomorphism between simple adjoint Chevalley groups can be expressed uniquely as the product of a ring isomorphism, a graph isomorphism and an inner automorphism. The isomorphisms between the elementary subgroups are also found having analogous expressions.
94.
P. Shumyatsky’s question 11.126 in the “Kourovka Notebook” is answered in the affirmative: it is proved that there exist a
constant c and a function of a positive integer argument f(m) such that if a finite group G admits an automorphism ϕ of order
4 having exactly m fixed points, then G has a normal series G ⩾ H ⩽ N such that |G/H| ⩽ f(m), the quotient group H/N is nilpotent
of class ⩽ 2, and the subgroup N is nilpotent of class ⩽ c (Thm. 1). As a corollary we show that if a locally finite group
G contains an element of order 4 with finite centralizer of order m, then G has the same kind of a series as in Theorem 1.
Theorem 1 generalizes Kovács’ theorem on locally finite groups with a regular automorphism of order 4, whereby such groups
are center-by-metabelian. Earlier, the first author proved that a finite 2-group with an almost regular automorphism of order
4 is almost center-by-metabelian. The proof of Theorem 1 is based on the authors’ previous works dealing in Lie rings with
an almost regular automorphism of order 4. Reduction to nilpotent groups is carried out by using Hall-Higman type theorems.
The proof also uses Theorem 2, which is of independent interest, stating that if a finite group S contains a nilpotent subgroup
T of class c and index |S: T | = n, then S contains also a characteristic nilpotent subgroup of class ⩽ c whose index is bounded
in terms of n and c. Previously, such an assertion has been known for Abelian subgroups, that is, for c = 1.
__________
Translated from Algebra i Logika, Vol. 45, No. 5, pp. 575–602, September–October, 2006. 相似文献
95.
Finite equilibrated 2-generated 2-groups 总被引:2,自引:0,他引:2
Gheorghe Silberberg 《Acta Mathematica Hungarica》2006,110(1-2):23-35
96.
根据对称群的基本性质以及第二同构定理,给出了通过添加生成元到P群来构造对称群的一个Sylow-p子群的定理,添加的生成元保证能够快速得到对称群的一个Sylow—p子群.根据第二西洛定理求出了所有共轭子群,即所有Sylow-p子群.针对求所有共轭子群过程中面临共轭子群出现重复的问题,利用正规化子的性质,找到使得两个Sylow-p子群共轭的元,保证每次求的Sylow-P子群不重复.将此算法应用于S1,实验表明该算法可操作性强,耗费时间少. 相似文献
97.
本文证明了下面主要结果:设G是n-可解群,π是一些素数之集,若对任意p∈∩π(G),(p,n(1-n))=1,则G的π-Hall子群的个数r=k1k2...kt,每ki≡1(modp),某P∈π,且每ki整除G的一个主因子。 相似文献
98.
Suppose that H is a subgroup of a finite group G. H is called π-quasinormal in G if it permutes with every Sylow subgroup of G; H is called π-quasinormally embedded in G provided every Sylow subgroup of H is a Sylow subgroup of some π-quasinormal subgroup of G; H is called c-supplemented in G if there exists a subgroup N of G such that G = HN and H ∩ N ⩽ H
G
= Core
G
(H). In this paper, finite groups G satisfying the condition that some kinds of subgroups of G are either π-quasinormally embedded or c-supplemented in G, are investigated, and theorems which unify some recent results are given.
相似文献
99.
Fuzzy同余和正规Fuzzy子群(英文) 总被引:1,自引:0,他引:1
自从A. Rosenfeld在1971年提出Fuzzy子群的概念以来,在Fuzzy群的研究方面已有不少进展,例如见[1,2,5,6,10,11,14]。另一方面,L.A.Zadeh首创的Fuzzy关系理论的研究也是硕果累累,例如见[3,4,8,12,13,15]。本文通过Fuzzy同余关系和正规Fuzzy子群的相互联系,将这两个方向的研究成果进行“嫁接”和“杂交”,得到许多有趣的结果。主要结果是定理2.7,定理3.1和3.6。本文另一主题是引入T-Fuzzy群的正规T-Fuzzy子群的新概念,当T是正则t-范算子时,得到了T-Fuzzy群的三个同构定理,作者认为它比现有的相应同构定理更为简洁、广泛和自然。 相似文献
100.
在本文,我们证明了:若群G满足Sz(22m+1)≤G≤AutSz(22m+1)m≥1,且G作用在2-(v.k.1)设计上是线本原的,则G也是点本原的. 相似文献