The following paper has been published
El siguiente artículo ha sido publicado
El següent article ha sigut publicat
A. Ballester-Bolinches, J. C. Beidleman, R. Esteban-Romero, and M. F. Ragland
Some local properties defining T0-groups and related classes of groups
Publ. Mat., 60(1):265–272, 2016
http://projecteuclid.org/euclid.pm/1450818490
Abstract
We call G a Hall_χ-group if there exists a normal nilpotent subgroup N of G for which G/N′ is an χ-group. We call G a T₀-group provided G/Φ(G) is a T-group, that is, one in which normality is a transitive relation. We present several new local classes of groups which locally define Hall_χ-groups and T₀-groups where χ∈{T, PT, PST}; the classes PT and PST denote, respectively, the classes of groups in which permutability and S-permutability are transitive relations.
2010 Mathematical Subject Classification: 20D10, 20D20, 20D35
Keywords: Subnormal subgroup, T-group, PST-group, finite solvable group

be a formation of finite groups. A subgroup M of a finite group G is said to be
-normal in G if G/CoreG(M) belongs to
. A subgroup U of a finite group G is called a K-
-subnormal subgroup of G if either U = G or there exist subgroups U = U0 ≤ U1 ≤ … ≤ Un = G such that Ui − 1 is either normal or
-normal in Ui, for i = 1, 2, …, n. The K-
-subnormality could be regarded as the natural extension of the subnormality to formation theory and plays an important role in the structural study of finite groups. The main purpose of this paper is to analyse classes of finite groups whose K-
-subnormal subgroups are exactly the subnormal ones. Some interesting extensions of well-known classes of groups emerge.
-subnormal Subgroup; Subnormal Subgroup; PST-groups; PT-groups; T-groups