Earlier, Brian Beesley wrote: > 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.
... to which Daran G. recently responded: > Not necessarily. The marginal benefit/cost ratio of doing factoring > work on exponant x awaiting a first time test, is twice what it > would be if exponant x were awaiting a DC. This does not mean that > it is greater that doing factoring work on exponant y which is > awaiting a DC. But ones factoring benefit calculation might ["should" would be in line with the popular theme of prescribing what's best for other GIMPS participants :)] include not only the time savings of eliminating the need for one or two L-L tests, but also the extra benefit of finding a specific factor. In the GIMPS Search Status table at www.mersenne.org/status.htm the march of progress is from "Status Unknown" to "Composite - One LL" to "Composite - Two LL" to ... "Composite - Factored". This reflects the view (with which I agree) that it is more valuable to know a specific factor of a Mnumber than to know that a Mnumber is composite but not to know any specific factor of that Mnumber. So a "Factored" status is better for GIMPS than a "Two LL" status, but calculations of factoring benefit that consider only the savings of L-L test elimination are neglecting the difference between those two statuses. If one consciously wants to neglect that difference ... well, okay ... but I prefer to see that explicitly acknowledged. Richard Woods _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
