On Sun, Oct 29, 2006 at 05:58:35PM +0000, david eddy wrote:
> Putting it through the FFT mill and getting an exact 48 bit integer is
> IMHO quite another:)

For the record, the relative error in a Cooley-Tukey FFT is bounded by O(ε
log N), (ε being 0.5 * 10^-49 here, AFAICS, and N being the transform
length); the average is about O(ε √log N). I'm not sure exactly which of
these estimates are actually used for Prime95, but I remember it was all
hashed out in a message to this list from Brian several years ago when George
asked, so it's all in good hands. :-)

/* Steinar */
-- 
Homepage: http://www.sesse.net/
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