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Scientific Part
Mathematics
$\Omega\zeta$-foliated Fitting classes
O. V. Kamozina Bryansk State Technological University of Engineering, 3 Stanke Dimitrova Ave., Bryansk 241037, Russia
Abstract:
All groups under consideration are assumed to be finite. For a nonempty subclass of
$\Omega$ of the class of all simple groups
$\frak I$ and the partition
$\zeta =\{\zeta_i\mid i\in I\}$, where
$\zeta_i$ is a nonempty subclass of the class
$\frak I$,
$\frak I =\cup_ {i\in I}\zeta _i$ and
$\zeta_i \cap \zeta_j = \varnothing$ for all
$i\not = j$,
$\Omega\zeta R$-function
$f$ and
$\Omega\zeta FR$-function
$\varphi$ are introduced. The domain of these functions is the set
$\Omega\zeta\cup \{\Omega '\}$, where $\Omega\zeta =\{\Omega\cap\zeta_i\mid\Omega\cap\zeta_i\not =\varnothing\}$,
$\Omega '=\frak I\setminus\Omega$. The scope of these function values is the set of Fitting classes and the set of nonempty Fitting formations, respectively. The functions
$f$ and
$\varphi$ are used to determine the
$\Omega\zeta$-foliated Fitting class $\frak F=\Omega\zeta R(f,\varphi )=(G: O^\Omega (G)\in f(\Omega' )$ and $G^{\varphi (\Omega\cap\zeta_i )}\in f(\Omega\cap\zeta_i )$ for all
$\Omega\cap\zeta_i \in\Omega\zeta (G))$ with
$\Omega\zeta$-satellite
$f$ and
$\Omega\zeta$-direction
$\varphi$. The paper gives examples of
$\Omega\zeta$-foliated Fitting classes. Two types of
$\Omega\zeta$-foliated Fitting classes are defined:
$\Omega\zeta$-free and
$\Omega\zeta$-canonical Fitting classes. Their directions are indicated by
$\varphi_0$ and
$\varphi_1$ respectively. It is shown that each non-empty non-identity Fitting class is a
$\Omega\zeta$-free Fitting class for some non-empty class
$\Omega\subseteq\frak I$ and any partition
$\zeta$. A series of properties of
$\Omega\zeta$-foliated Fitting classes is obtained. In particular, the definition of internal {
$\Omega\zeta$-sa}tellite is given and it is shown that every
$\Omega\zeta$-foliated Fitting class has an internal
$\Omega\zeta$-satellite. For
$\Omega=\frak I$, the concept of a
$\zeta$-foliated Fitting class is introduced. The connection conditions between
$\Omega\zeta$-foliated and
$\zeta$-foliated Fitting classes are shown.
Key words:
finite group, Fitting class, $\Omega\zeta$-foliated, $\Omega\zeta$-satellite, $\Omega\zeta$-direction.
UDC:
512.542 Received: 17.11.2019
Accepted: 15.01.2020
DOI:
10.18500/1816-9791-2020-20-4-424-433