On 6 Apr 00, at 20:48, Nathan Russell wrote:
> These exponents originate from a user that has been doing factoring to
> small depths on several hundred, if not thousand, exponents. Check the
> list archives from about 2 weeks ago.
Actually PrimeNet should take care of that problem itself. There
always have been, for some reason, some exponents which get assigned
as LL tests or even double checks which are factored short. George's
programs simply do the required factoring before going on to the LL
test - unless a factor is found 8-)
> Does anyone have a solution? Until one is found, I would suggest
> contacting George to get assignments that have been factored deeper
> ([EMAIL PROTECTED]), or using the machine for double-checking for a
> little while.
Or try picking up exponents shortly after 0600 GMT for reasons which
have been explained previously.
> I don't know if PrimeNet will allow another user to factor
> exponents that have been checked out to you and nevertheless accept the LL
> results from you without you having run factoring. Maybe Scott or one of
> the other PrimeNet people could answer this for you.
If I take an assignment from PrimeNet, there's nothing to stop me
subcontracting any trial factoring to a third party. The third party
probably won't get credit for the factoring work done, but neither
will I.
However, most people in Bill Rea's position will be able to find a PC
lying around somewhere & should be able to do the factoring work on
that. A PC well short of the current state of the art should be able
to do trial factoring fast enough to keep a Sun E450 system running
Mlucas supplied with prefactored LL assignments, without having to
work more than one day a week!
There are also factoring programs available in portable high-level-
language source format, in particular look for Mfactor.c If it wasn't
for the fact that factoring is so far ahead of LL testing, I'd
probably switch my Alpha system to factoring - with its 64 bit
integer registers and quad-issue pipeline, the architecture is much
better suited to factoring than LL testing, and the performance is
somewhat startling for factoring (up to 63 bits) even though the
program is neither tuned to the hardware nor hand optimized.
Regards
Brian Beesley
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