Recursive solution

Im not sure that my solution is recursive or not,Im perfoming an operation on 2 numbers each time,I’m tunneling one less bit to a consecutive auxiliary functuon in the same file and than returning the result.Yet each auxiliary function returns the result instantly and not only after it has reached the base condition.I hope I was clear enough and I hope you could help me clarify more how my solution should look like

If I understand correctly, what you’re doing is something like this:

f(4) = f(3) \circ 0\\ f(3) = k[2:1]

where k[2:1] is some constant.

If that is the case, your solution doesn’t follow the given recursive formulation.
You need to use b2g3 in b2g4, b2g2 in b2g3, b2g1 in b2g2.
b2g1 should be your base case.