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_S A B G L :
A != set0 -> L \subset 'N(A) -> A \subset B -> normedTI B G L ->
normedTI A G L.