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Problemy Fiziki, Matematiki i Tekhniki (Problems of Physics, Mathematics and Technics), 2020, Issue 4(45), Pages 91–94
(Mi pfmt751)
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MATHEMATICS
On the centralizer of the σ-nilpotent residual of the σ-subnormal subgroup
I. M. Dergacheva, I. P. Shabalina, E. A. Zadorozhnyuk Belarusian State University of Transport, Gomel
Abstract:
Throughout this paper, all groups are finite and G always denotes a finite group. Moreover, σ is some partition of the set of all
primes P, that is, σ={σi∣i∈I}, where P=⋃i∈Iσi and σi∩σj=∅ for all i≠j. The group G is said to be: σ-primary if G
is a σi-group for some i; σ-nilpotent if every chief factor H/K of G is σ-central in G, that is, (H/K)⋊(G/CG(H/K)) is σ-primary. The symbol GNσ denotes the σ-nilpotent residual of G, that is, the intersection of all normal subgroups N of G such that G/N is σ-nilpotent; Zσ(G) is the σ-nilpotent hypercentre of G, that is, the product of all normal subgroups N of G such that either N=1 of N≠1 and every chief factor of G below N is σ-central in G. A subgroup A of G is said to be σ-subnormal in G if there is a subgroup chain A=A_0\leqslant A_1\leqslant\dots\leqslant A_n=G such that either A_{i-1}\unlhd A_i or A_i/(A_{i-1})_{A_i} is \sigma-primary for all i=1,\dots,n. In this paper, we prove that if S be a \sigma-subnormal subgroup of G and Z_\sigma(E)=1 for every subgroup E of G such that S\leqslant E, then C_G(S^{\mathfrak{N}_\sigma})\leqslant S^{\mathfrak{N}_\sigma}.
Keywords:
finite group, \sigma-nilpotent group, \sigma-subnormal subgroup, \sigma-nilpotent residual of a finite group, \sigma-nilpotent hypercentre.
Received: 31.10.2020
Citation:
I. M. Dergacheva, I. P. Shabalina, E. A. Zadorozhnyuk, “On the centralizer of the \sigma-nilpotent residual of the \sigma-subnormal subgroup”, PFMT, 2020, no. 4(45), 91–94
Linking options:
https://www.mathnet.ru/eng/pfmt751 https://www.mathnet.ru/eng/pfmt/y2020/i4/p91
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Abstract page: | 109 | Full-text PDF : | 40 | References: | 27 |
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