At 06:58 PM 11/8/2002 -0500, [EMAIL PROTECTED] wrote:
The first of these is slightly larger than 2^65, so it was likely cheaper to find via p-1 than via sieving. But the second is only a tad larger than 2^63, i.e. under the hardware long int length, and thus sieving to 2^64 should have been quite fast. George - is it faster to do p-1 for numbers this size than to sieve to 2^64?
This has been discussed on the list before. It is actually better to do the P-1 factoring before doing the last one or two bits of trial factoring. It is a small optimization, but maybe one day it could be implemented.
_________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
