On 12 Nov 2001, at 23:34, [EMAIL PROTECTED] wrote: > Many recent double-check assignments involve a second round of > factoring because (a) the trial-factoring breakpoints are higher now > than they were when the first L-L test was assigned, and/or (b) P-1 > factoring had not yet been implemented in Prime95 when they were > assigned for initial L-L tests. Consequent elimination of once-L-Led > Mnumbers by second-round factoring would account for some of the > difference, though I doubt there've been 30,000.
Nothing like 30,000! The probability of finding a factor by going one bit deeper (given that trial factoring is already completed to ~60 bits) is less than 0.02; the probability of finding a factor using P-1 with "double checking" limits is typically 0.025 (variable depending on how deeply trial factoring has been done). 70,000 double check assignments would be expected to find about 2,000 factors. > > In addition, some folks have concentrated on factoring Mnumbers that > have been L-L tested but not yet DC'd, specifically in order to reduce > the number of necessary double-checks. Eh? Doesn't it make more sense to concentrate on factoring Mnumbers that haven't yet been L-L tested? That way "success" in finding a factor reduces the number of LL tests, as well as (eventually) the number of double checks. Regards Brian Beesley _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
