Hmm yes I suppose I was a bit sloppy, although I got the gist of it right somehow. I guess the problem here is that x^4 = 1 mod 2 is false if x = 0 mod 2, but x

Hmm yes I suppose I was a bit sloppy, although I got the gist of it right somehow. I guess the problem here is that x^4 = 1 mod 2 is false if x = 0 mod 2, but x^5 = x mod 2 does hold for all numbers. I've fixed the problems you mentioned, thanks.