共查询到20条相似文献,搜索用时 13 毫秒
1.
2.
We give a characterisations for an abstract group to be an S-arithmetic group of a higher rank semi-simple group. 相似文献
3.
We present a new characterisation of Goursat categories in terms of special kind of pushouts, that we call Goursat pushouts. This allows one to prove that, for a regular category, the Goursat property is actually equivalent to the validity of the
denormalised 3-by-3 Lemma. Goursat pushouts are also useful to clarify, from a categorical perspective, the existence of the
quaternary operations characterising 3-permutable varieties. 相似文献
4.
5.
6.
设p为奇素数,本文给出了中心循环中心商的阶小于p^5的有限p-群的完全分类并且给出它们中无对合自同构的群的自同构群的阶。由此,我们找到了能作为有限群自同构群的p^mq^n阶群和p^n阶群,统一和推广了Curran在1988年和Caranti与Scoppola在1990年的文章的所有结果。 相似文献
7.
本文给出了Dedekind群的一个刻画.即如果一个群G有一个无不动点的弱幂同构,则G是一个Dedekind群. 相似文献
8.
Gerhard Pazderski 《Mathematische Nachrichten》1992,155(1):111-125
9.
We study the class of cyclically presented groups which contain Fibonacci groups and Sieradski groups. Conditions are specified for these groups to be finite, pairwise isomorphic, or aspherical. As a partial answer to the question of Cavicchioli, Hegenbarth, and Repov, it is stated that there exists a wide subclass of groups with an odd number of generators cannot appear as fundamental groups of hyperbolic three-dimensional manifolds of finite volume. 相似文献
11.
Siaw-Lynn Ng 《Order》2004,21(1):1-5
We present a characterisation of posets of size n with linear discrepancy n − 2. These are the posets that are “furthest” from a linear order without being an antichain.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
12.
We study the dependence of the structure of finite p-soluble groups on the indices of normalizers of Sylow subgroups. We obtain estimates for the p-length of these groups, and for small values of indices we find the nilpotent length of a soluble group. 相似文献
13.
Algebras and Representation Theory - A pair (A, P) is called a cover of EndA(P)op if the Schur functor HomA(P,?) is fully faithful on the full subcategory of projective A-modules, for a given... 相似文献
14.
A locally compact group G is called a Tortrat group if for any probability measure on G which is not idempotent, the closure of {gg
–1 | gG} does not contain any idempotent measure. We show that a connected Lie group G is a Tortrat group if and only if for all gG all eigenvalues of Ad g are of absolute value 1. Together with well-known results this also implies that a connected locally compact group is a Tortrat group if and only if it is of polynomial growth. 相似文献
15.
This paper considers such a group G which possesses nontrivial proper subgroups H 1 ,H 2 such that any proper subgroup of G not contained in H 1 ∪ H 2 is p-closed and obtains that if G is soluble,then the number of prime divisors contained in |G| is 2,3 or 4;if not,then it has a form x N where N/Φ(N) is a non-abelian simple group.Then the structure of such a group is determined for p = 2,H 1 = H 2 under some conditions. 相似文献
16.
A. Martínez-Pastor 《Acta Mathematica Hungarica》1999,82(1-2):21-33
Given a fixed finite group S, we define different versions of S-stability and S-constraint. Then we use them to find a non-trivial characteristic subgroup W*(S) of S which is normal and self-centralizing in every finite S-stable and S-constrained group H containing S. Moreover, W*(S) contains every abelian subgroup of S normalized by W*(S). 相似文献
17.
Wolfgang Alexander Moens 《代数通讯》2013,41(7):2427-2440
Jacobson proved that if a Lie algebra admits an invertible derivation, it must be nilpotent. He also suspected, though incorrectly, that the converse might be true: that every nilpotent Lie algebra has an invertible derivation. We prove that a Lie algebra is nilpotent if and only if it admits an invertible Leibniz-derivation. The proofs are elementary in nature and are based on well-known techniques. We only consider finite-dimensional Lie algebras over a fields of characteristic zero. 相似文献
18.
We give a 2-track-theoretical characterisation of the homotopy pushout of a 3-corner by recognising the mapping 2-simplex as an initial object in a coherent homotopy category of Hausdorff spaces under a 3-corner with morphisms expressed in terms of the 1-morphisms and 2-morphisms of a homotopy 2-groupoid. 相似文献
19.
In the past thirty years, several kinds of quantitative characterizations of finite groups especially finite simple groups have been investigated by many mathematicians. Such as quantitative characterizations by group order and element orders, by element orders alone, by the set of sizes of conjugacy classes, by dimensions of irreducible characters, by the set of orders of maximal abelian subgroups and so on. Here the authors continue this topic in a new area tending to characterize finite simple groups with given orders by some special conjugacy class sizes, such as largest conjugacy class sizes, smallest conjugacy class sizes greater than 1 and so on. 相似文献
20.
We study the dependence of the structure of finite p-soluble groups on the indices of normalizers of Sylow subgroups. We obtain estimates for the p-length of these groups, and for small values of indices we find the nilpotent length of a soluble group. 相似文献