Automorphism group is really a group

[rbeezer]

Exercise 11.5.1 (in Additional Exercises) id homomorph-exercise-aut-G

Do you want to say the group operation is composition? Just to be clear what the automorphism group is exactly.

Problem has \leq where maybe you want \subseteq or similar?

Should $G$ be finite if you want an automorphism to be construed as a permutation?