Section FrobeniusBasics.
Variable gT : finGroupType.
Implicit Types (A B : {set gT}) (G H K L R X : {group gT}).
Arguments normedTI_P {A G L}.

Lemma normedTI_memJ_P A G L :
reflect [/\ A != set0, L \subset G
& {in A & G, forall a g, (a ^ g \in A) = (g \in L)}]
(normedTI A G L).