On - and -decomposable finite groups
A finite solvable group G is called an X-group if the subnormal subgroups of G permute with all the system normalizers of G. It is our purpose here to determine some of the properties of X-groups. Subgroups and quotient groups of X-groups are X-groups. Let M and N be normal subgroups of a group G of relatively prime order. If G/M and G/N are X-groups, then G is also an X-group. Let the nilpotent residual L of G be abelian. Then G is an X-group if and only if G acts by conjugation on L as a group...
By constructing appropriate faithful simple modules for the group GL(2,3), the author shows that certain "local" definitions for formations are not equivalent.
A theorem of Burnside asserts that a finite group is -nilpotent if for some prime a Sylow -subgroup of lies in the center of its normalizer. In this paper, let be a finite group and the smallest prime divisor of , the order of . Let . As a generalization of Burnside’s theorem, it is shown that if every non-cyclic -subgroup of is self-normalizing or normal in then is solvable. In particular, if , where for and for , then is -nilpotent or -closed.
In this paper we consider finite loops of specific order and we show that certain abelian groups are not isomorphic to inner mapping groups of these loops. By using our results we are able to construct a finite solvable group of order 120 which is not isomorphic to the multiplication group of a finite loop.
A subgroup of a group is said to be complemented in if there exists a subgroup of such that and . In this paper we determine the structure of finite groups with some complemented primary subgroups, and obtain some new results about -nilpotent groups.
Let be a finite group. A normal subgroup of is a union of several -conjugacy classes, and it is called -decomposable in if it is a union of distinct -conjugacy classes. In this paper, we first classify finite non-perfect groups satisfying the condition that the numbers of conjugacy classes contained in its non-trivial normal subgroups are two consecutive positive integers, and we later prove that there is no non-perfect group such that the numbers of conjugacy classes contained in its...
Let be a finite group with a dicyclic subgroup . We show that if there exist -connected transversals in , then is a solvable group. We apply this result to loop theory and show that if the inner mapping group of a finite loop is dicyclic, then is a solvable loop. We also discuss a more general solvability criterion in the case where is a certain type of a direct product.
We show that finite commutative inverse property loops may not have nonabelian dihedral 2-groups as their inner mapping group.
The major aim of the present paper is to strengthen a nice result of Shemetkov and Skiba which gives some conditions under which every non-Frattini G-chief factor of a normal subgroup E of a finite group G is cyclic. As applications, some recent known results are generalized and unified.
The intention of this paper is to provide an elementary proof of the following known results: Let G be a finite group of the form G = AB. If A is abelian and B has a nilpotent subgroup of index at most 2, then G is soluble.
We show that finite commutative inverse property loops with elementary abelian inner mapping groups of order are centrally nilpotent of class at most two.
We show that finite commutative inverse property loops with elementary abelian inner mapping groups of order are centrally nilpotent of class at most two.