Excellent Marcel !
I suspected you had made the same mistake I did when I first looked at
So, now the period (order) of rnd is established. That makes many
things easier. In particular, I am working on inverse-rnd by way of
Nth-iterate by way of b-functions. In the process I'll also find
b-functions are slower to evaluate, but easier to compose in this case
(only 32 binary terms in any iterate and each equation will fit into 32
bits because of the xors).
I'll show the results here soon.
Happy Forthing, Marcel.