# Math Help - Normalizer

1. ## Normalizer

Can u give me the definition of the $N_{Aut(A)}(B)$ where B is a subgrroup of A.

2. $N_A(B)=\{a\in A:aBa^{-1}=B\}$

3. ## normlizer

Yes this is the normalizer of the groups A and B. But I want to know the normalizer of automorphism of A in B.