On Thursday 12 June 2003 10:07, Nathan Russell wrote: > > That is a collosal understatement. Every modulo operation destroys > information, and I'm not sure whether one COULD construct such a file.
Indeed. In general there will be more than one x such that x^2-2 = R modulo 2^p-1 so, working backwards through a number of steps, you would have only a very small probability of deriving the same "starting condition". Even if the equation was easy to solve in reverse... Regards Brian Beesley _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers