0000000000976818
AUTHOR
Yangming Li
On partial CAP-subgroups of finite groups
Abstract Given a chief factor H / K of a finite group G, we say that a subgroup A of G avoids H / K if H ∩ A = K ∩ A ; if H A = K A , then we say that A covers H / K . If A either covers or avoids the chief factors of some given chief series of G, we say that A is a partial CAP-subgroup of G. Assume that G has a Sylow p-subgroup of order exceeding p k . If every subgroup of order p k , where k ≥ 1 , and every subgroup of order 4 (when p k = 2 and the Sylow 2-subgroups are non-abelian) are partial CAP-subgroups of G, then G is p-soluble of p-length at most 1.
On second minimal subgroups of Sylow subgroups of finite groups
A subgroup H of a finite group G is a partial CAP-subgroup of G if there is a chief series of G such that H either covers or avoids its chief factors. Partial cover and avoidance property has turned out to be very useful to clear up the group structure. In this paper, finite groups in which the second minimal subgroups of their Sylow p-subgroups, p a fixed prime, are partial CAP-subgroups are completely classified.
On self-normalising subgroups of finite groups
[EN] The aim of this paper is to characterise the classes of groups in which every subnormal subgroup is normal, permutable, or S-permutable by the embedding of the subgroups (respectively, subgroups of prime power order) in their normal, permutable, or S-permutable closure, respectively.
On the supersoluble hypercentre of a finite group
[EN] We give some sufficient conditions for a normal p-subgroup P of a finite group G to have every G-chief factor below it cyclic. The S-permutability of some p-subgroups of O^p(G)plays an important role. Some known results can be reproved and some others appear as corollaries of our main theorems.