> I think I know the answer to this... but want to > double-check to be sure... > > While doing factoring... using ECM... factors up to: > 15 digits is the equivalent of ~2^50... > 20 digits is the equivalent of ~2^67... > 25 digits is the equivalent of ~2^83... > 30 digits is the equivalent of ~2^100... > > If trial-factoring has been done up to 2^68... is it > possible to skip testing ECM curves for factors up to 15 > and/or 20 digits... and go straight to testing ECM curves > for digits up to 25 digits???
Makes sense to me, as long as you realise that the estimates for ECM factoring are just that, only estimates. Sometimes you get lucky and find a big factor with a small number of curves at a small B1 and sometimes you get unlucky and miss a small factor after a lot of effort. Personally, I would go straight in at the 25+ digits level. Paul _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
