I think I am really confusing myself with this problem. Here it is:

The formal system A consists of:

alphabet: 0 /

axiom: 0

inference rule: if x is a A-theorem, then so is x/

It asks for me to state a few theorems of this system. Am I right in thinking that 0/, 00/, 000/, 000//, 00// could all be examples of theorems?

It continues: Using the theorems of the A-system, we define a new B-system which consists of:

alphabet: 0,/,[,],>

axiom: Any A-theorem

inference rule: if x and y are B-theorems, then so is [x>y]

It asks again to state a few theorems of this system. Could some examples be [0/>00/], [00//>000/], [0/>0/]

Any help is really appreciated!