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141.
n-极大子群为共轭可换的有限群 总被引:2,自引:0,他引:2
赵俊英 《纯粹数学与应用数学》2004,20(2):177-181
群G的子群H称为G的共轭可换子群,若HHg=HgH,对任意g∈G都成立,本文考查了n-极大子群为共轭可换时对有限群构造的影响. 相似文献
142.
For a fundamental group of a compact orientable manifold, a condition is specified that is sufficient to guarantee the presence
of a “virtual” epimorphism onto a free non-Abelian group. A consequence is deriving a strong Tits alternative. An arbitrary
noncompact finitely generated discrete subgroup in PO(3, 1) either is large or is virtually Abelian. An application is provided
to the problem of uniform exponential growth for lattices in a 3-dimensional hyperbolic space and of growth of Betti numbers
for lattices in a hyperbolic n-dimensional space, where n is an odd number.
Supported by RFBR (project No. 08-01-00067), by DFG grant Gr 627-11, and by Forschergruppe “Spektrale Analysis, asymptotical
Verteilungen und stochastische Dynamiken,” Billfold University. (G. A. Noskov)
Translated from Algebra i Logika, Vol. 48, No. 2, pp. 174–189, March–April, 2009. 相似文献
143.
The question of existence of a maximal subgroup in the multiplicative group D* of a division algebra D finite-dimensional over its center F is investigated. We prove that if D* has no maximal subgroup, then deg(D) is not a power of 2, F*2 is divisible, and for each odd prime p dividing deg(D), there exist noncyclic division algebras of degree p over F. 相似文献
144.
Jakob Jonsson 《Journal of Algebraic Combinatorics》2009,29(1):81-90
J.L. Andersen proved that there is 5-torsion in the bottom nonvanishing homology group of the simplicial complex of graphs
of degree at most two on seven vertices. We use this result to demonstrate that there is 5-torsion also in the bottom nonvanishing
homology group of the matching complex
on 14 vertices. Combining our observation with results due to Bouc and to Shareshian and Wachs, we conclude that the case
n=14 is exceptional; for all other n, the torsion subgroup of the bottom nonvanishing homology group has exponent three or is zero. The possibility remains that
there is other torsion than 3-torsion in higher-degree homology groups of
when n≥13 and n≠14.
Research of J. Jonsson was supported by European Graduate Program “Combinatorics, Geometry, and Computation”, DFG-GRK 588/2. 相似文献
145.
A subgroup H of a group G is said to have the sub-cover-avoidance property in G ffthereis a chief series 1 = G0 ≤ G1 ≤…≤ Gn - G, such that Gi-1(H ∩ Gi) G for every i = 1,2,... ,l. In this paper, we give some characteristic conditions for a group to be solvable under the assumptions that some subgroups of a group satisfy the sub-cover-avoidance property. 相似文献
146.
147.
148.
Juan Pablo Navarrete Waldemar Barrera 《Bulletin of the Brazilian Mathematical Society》2009,40(1):99-106
In this paper, we prove following: If G ⊂ PU (2, 1) is an infinite, discrete group, acting on Pℂ2 without complex invariant lines, then the component containing ℍPℂ2 of the domain of discontinuity Ω(G) = PPℂ2∖ Λ (G), according to Kulkarni, is G-invariant complete Kobayashi hyperbolic.
The authors were supported by the Universidad Autónoma de Yucatán and the Universidad Nacional Autónoma de México. 相似文献
149.
A finite group G is called an MSN-group if all maximal subgroups of the Sylow subgroups of G are subnormal in G. In this paper, we determinate the structure of non-MSN-groups in which all of whose proper subgroups are MSN-groups. 相似文献
150.
利用计算机,在GAP的环境下进行编程,计算出对称群S10共有1 593个共轭子群类,29594446个子群.其中循环群有42个共轭子群类,可解群有1 418个共轭子群类,幂零群有531个共轭子群类,超可解群有923个共轭子群类,并且通过本文中的表信息可计算出S10中各阶子群的个数及各共轭子群类中所含子群的个数. 相似文献