Finding invertible permutation functions

[Sarad AV]

hi,

I am looking at single cycle, invertible permutation
functions of the form
x ->  x+ (x^2 V C)  (mod 2^n), where V is a bitwise OR
and C is a special constant.
This function is as given in the url below
http://citeseer.ist.psu.edu/klimov02new.html

Would like to find the inverse permutation function
for it but the paper only shows that the above
function is provably invertible.

Are  there any construction methods for finding
inverse permutation function, for a single cycle
invertible function f?

Thanks,
Sarad.


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