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61.
62.
In this paper, we deal mainly with the following problem: if every 2-maximal subgroup of a Sylow p-subgroup of a finite group G is S-seminormal in G, what conditions force G to be p-nilpotent? As an application of main results, some sufficient conditions for finite nilpotent groups and finite supersolvable groups are obtained. 相似文献
63.
V. S. Monakhov 《Mathematical Notes》1997,61(5):585-589
Finite groups with 2-nilpotent subgroups of even index are described.
Translated fromMatematicheskie Zametki, Vol. 61, No. 5, pp. 700–705, May, 1997.
Translated by A. I. Shtern 相似文献
64.
We prove the existence of infinite subgroups with nontrivial locally finite radicals and of infinite locally finite subgroups in the groups with almost finite almost solvable elements of order 2 and 4 and in the groups with almost finite elements. 相似文献
65.
V. S. Monakhov 《Mathematical Notes》2006,80(3-4):542-549
Tests for π-solvability of a finite group with seminormal Hall π-subgroup are established and the nilpotency of the third commutator subgroup of any group with seminormal noncyclic Sylow subgroups is proved. 相似文献
66.
Aaron Heap 《Topology》2006,45(5):851-886
We define new bordism and spin bordism invariants of certain subgroups of the mapping class group of a surface. In particular, they are invariants of the Johnson filtration of the mapping class group. The second and third terms of this filtration are the well-known Torelli group and Johnson subgroup, respectively. We introduce a new representation in terms of spin bordism, and we prove that this single representation contains all of the information given by the Johnson homomorphism, the Birman-Craggs homomorphism, and the Morita homomorphism. 相似文献
67.
Crystal Structure of Cesium Phenylacetylide,CsC2C6H5, Solved and Refined from Synchrotron Powder Diffraction Data 下载免费PDF全文
The crystal structure of cesium phenylacetylide, CsC2C6H5, was solved and refined from synchrotron powder diffraction data (Pbca, Z = 8). Each Cs+ cation is coordinated by five ligands: four acetylide groups coordinate side‐on and one end‐on. A similar arrangement is found in the crystal structure of NaC2H (P4/nmm, Z = 2). There is a group‐subgroup relationship between both structures. Most importantly, the crystal structure of CsC2C6H5 could only be solved with the help of synchrotron data, as the very good peak:noise ratio allowed the assignment of several very weak reflections, which finally led to the correct space group, in which a structural solution was possible using direct space methods. 相似文献
68.
69.
A. O. Asar 《代数通讯》2017,45(6):2690-2707
In this work the study of subgroups of totally imprimitive permutation groups is continued. Some sufficient conditions for the existence of minimal non-FC-subgroups are given. These results depend mainly on the properties of self-normalizing subgroups, which are closed in the topology of point-wise convergence. Finally, new properties of a totally imprimitive permutation p-group satisfying the cyclic-block property are given which might be a suitable example to look for minimal non-FC-subgroups. 相似文献
70.
Juping Tang 《代数通讯》2017,45(7):3017-3021
A subgroup A of a finite group G is called {1≤G}-embedded in G if for each two subgroups K≤H of G, where K is a maximal subgroup of H, A either covers the pair (K,H) or avoids it. Moreover, a subgroup H of G is called nearly m-embedded in G if G has a subgroup T and a {1≤G}-embedded subgroup C such that G?=?HT and H∩T≤C≤H. In this paper, we mainly prove that G is solvable if and only if its Sylow 3-subgroups, Sylow 5-subgroups and Sylow 7-subgroups are nearly m-embedded in G. 相似文献