Тип публикации: статья из журнала
Год издания: 2017
Идентификатор DOI: 10.1134/S0081543817020134
Ключевые слова: complement of a subgroup, finite simple group, pronormal subgroup, subgroup of odd index, supplement of a subgroup
Аннотация: A subgroup H of a group G is called pronormal if, for any element g ∈ G, the subgroups H and Hg are conjugate in the subgroup H,Hg. We prove that, if a group G has a normal abelian subgroup V and a subgroup H such that G = HV, then H is pronormal in G if and only if U = NU(H)[H,U] for any H-invariant subgroup U of V. Using this facПоказать полностьюt, we prove that the simple symplectic group PSp6n(q) with q ≡ ±3 (mod 8) contains a nonpronormal subgroup of odd index. Hence, we disprove the conjecture on the pronormality of subgroups of odd indices in finite simple groups, which was formulated in 2012 by E.P. Vdovin and D.O. Revin and verified by the authors in 2015 for many families of simple finite groups. © 2017, Pleiades Publishing, Ltd.
Журнал: Proceedings of the Steklov Institute of Mathematics
Выпуск журнала: Vol. 296
Номера страниц: 145-150
ISSN журнала: 00815438
Издатель: Maik Nauka-Interperiodica Publishing