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Adolfo Ballester-Bolinches, Luis M. Ezquerro, Ning Su, and Yanming Wang.

On the focal subgroup of a saturated fusion system.

J. Algebra, 468:72–79, 2016

https://doi.org/10.1016/j.jalgebra.2016.07.034

Abstract

The influence of the cyclic subgroups of order p or 4 of the focal subgroup of a saturated fusion system F over a p-group S is investigated in this paper. Some criteria for normality of S in F as well as necessary and sufficient conditions for nilpotency of F are given. The resistance of a p-group in which every cyclic subgroup of order p or 4 is normal, and earlier results about p-nilpotence of finite groups and nilpotency of saturated fusion systems are consequences of our study.

2010 Mathematical Subject Classification: 20C20

Keywords: Saturated fusion system, Control of fusion