排序方式: 共有37条查询结果,搜索用时 15 毫秒
1.
《Discrete Mathematics》2019,342(1):233-249
A Weyl arrangement is the hyperplane arrangement defined by a root system. Saito proved that every Weyl arrangement is free. The Weyl subarrangements of type are represented by simple graphs. Stanley gave a characterization of freeness for this type of arrangements in terms of their graph. In addition, the Weyl subarrangements of type can be represented by signed graphs. A characterization of freeness for them is not known. However, characterizations of freeness for a few restricted classes are known. For instance, Edelman and Reiner characterized the freeness of the arrangements between type and type . In this paper, we give a characterization of the freeness and supersolvability of the Weyl subarrangements of type under certain assumption. 相似文献
2.
Riccardo Biagioli 《Discrete Mathematics》2005,296(1):1-13
Some posets of binary leaf-labeled trees are shown to be supersolvable lattices and explicit EL-labelings are given. Their characteristic polynomials are computed, recovering their known factorization in a different way. 相似文献
3.
J. Cimprič 《代数通讯》2013,41(1):103-119
A subgroup H is called Q-supplemented in a finite group G, if there exists a subgroup K of G such that G = HK and H ∩ K is contained in H QG , where H QG is the maximal quasinormal subgroup of G contained in H. In this article, we investigate the influence of Q-supplementation of some primary subgroups in finite groups. Some recent results are generalized. 相似文献
4.
In (2009), Towers [10] presented the notion of c-ideality of a subalgebra of a Lie algebra, and gave some characterizations of solvable and supersolvable Lie algebras. In this article, we further investigate the influence of c-ideality of some subalgebras on the structure of Lie algebras. We also obtain some equivalent conditions for supersolvability of a finite dimensional Lie algebra. 相似文献
5.
Drew Armstrong 《Journal of Combinatorial Theory, Series A》2009,116(8):1285-1305
Let (W,S) be an arbitrary Coxeter system. For each word ω in the generators we define a partial order—called the ω-sorting order—on the set of group elements Wω⊆W that occur as subwords of ω. We show that the ω-sorting order is a supersolvable join-distributive lattice and that it is strictly between the weak and Bruhat orders on the group. Moreover, the ω-sorting order is a “maximal lattice” in the sense that the addition of any collection of Bruhat covers results in a nonlattice.Along the way we define a class of structures called supersolvable antimatroids and we show that these are equivalent to the class of supersolvable join-distributive lattices. 相似文献
6.
极小子群对有限群结构的影响 总被引:6,自引:0,他引:6
设G是一个有限群.G的极小子群如何影响群的结构是一个人们感兴趣的问题.在本文中,我们用极小子群的c-正规的条件刻划群G的结构.我们推广了一些已知的结果. 相似文献
7.
8.
某些子群是半正规的有限群 总被引:6,自引:0,他引:6
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 相似文献
9.
设F是可解的,子群闭的,由{f(P)}所局部定义的群系,Fp是由{f(q)}定义的p-局部定义群系.N为幂零群系.本文证明了:1)设F满足:任一群属于F,当且仅当,对每p.其p-Sylow-正规化子属于Fp.于是“群G∈N.F(幂零由F的扩张)的充要条件是,对每P,其p-Sylow-正规化子的Fp剩余次正规于G内.2)群G为超可解的充要条件是,对每p,其p-Sylow-正规化子为p-超可解,且其幂零剩余次正规于G内.若对每p,群G的p-Sylow子群无商群与p2-次对称群的p-Sylow子群同构,则称G为B-群.3)设G为B-群,又群系F含于σ-Sylow塔群系内.于是①G∈F,当且仅当,对每p,G的p-Sylow-正规化属于Fp;②G∈N·F,当且仅当,对每p,G的p-Sylow-正规化子的Fp剩余在G内次正规. 相似文献
10.