Finite coverings by cosets of normal subgroups

Parmenter, M. M.

doi:10.1090/S0002-9939-1990-1039536-5

Finite coverings by cosets of normal subgroups
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Proc. Amer. Math. Soc. 110 (1990), 877-880 Request permission

Abstract:

In this brief note, we characterize those groups $G$ which can be covered by finitely many cosets ${a_i}{M_i}$ of maximal normal subgroups ${M_i}$, where the covering is irredundant and not all ${M_i}$ are equal. This refines an earlier result of Brodie, Chamberlain, and Kappe, who characterized those groups which can be covered by finitely many proper normal subgroups.

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Research problem no.

17

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