Hi all! I have an urgent question:

Let L be a permutation of GF(2^6). (For example; L(x)=x^6)

I need to find a formula for the inverse of such polynomials.

Is it possible to do this on MAGMA?

p.s: I've tried this one:

1) Define L(x)=x^6 as a polynomial in the ring GF(2^6)[x]

2) Define a function f as the evaluation map of L

3) Define the inverse of this map as "g:=Inverse(f)".

However, when I wish to calculate the values such as "g(0), g(1), ...", it says "there's no rule for calculating preimage"