Abstract
A primary covering of a finite group ๐บ is a family of proper subgroups of ๐บ whose union contains the set of elements of ๐บ having order a prime power.
We denote by
Funding source: Fundaรงรฃo de Apoio ร Pesquisa do Distrito Federal
Award Identifier / Grant number: 03/2016
Funding source: Conselho Nacional de Desenvolvimento Cientรญfico e Tecnolรณgico
Award Identifier / Grant number: 302134/2018-2
Award Identifier / Grant number: 422202/2018-5
Funding statement: M. Garonzi was supported by Fundaรงรฃo de Apoio ร Pesquisa do Distrito Federal (FAPDF) โ demanda espontรขnea 03/2016, and by Conselho Nacional de Desenvolvimento Cientรญfico e Tecnolรณgico (CNPq) โ Grant numbers 302134/2018-2, 422202/2018-5.
Acknowledgements
The authors are grateful to the referee for the careful reading of the paper and for completing the calculations of
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Communicated by: Evgeny Vdovin
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