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Old 2007-12-21, 23:44   #4
gd_barnes's Avatar
May 2007
Kansas; USA

3·7·491 Posts

Originally Posted by Anonymous View Post
Does this include the two k's I'm working on? If so, what happens if I find a prime before I reach n=100k? Does that mean that your sieving work for those k's will have been wasted?

FYI: If I reach n=100k on my two k's without finding a prime, I'll release them, so you can go ahead include them in a drive from n=100k on.
Yes it does but only from n=100K-200K. The same thing for the other k that has been reserved. If you or anyone else finds a prime on a k that I'm sieving to a high range, I'll just use srfile to delete the k from the big sieve.

The issue of wasted sieving effort affects all conjecture projects. There's no way around it while still maintaining efficient sieving. If you sieve n=25K-100K and find a prime at n=25001, then the sieving effort is technically wasted if you don't use it. That said, if we're in top-5000 territory, let's say someone is sieving n=100K-200K and they find a prime at n=100001 base 16, then I'd encourage them to continue if what they're after is top-5000 primes, even though it doesn't contribute to this effort. (And if we become an official prime-search project, any top-5000 primes DO add to our score at Prof. Keller's site and I'm all for that!) But if people want to work on proving the conjecture then they can stop and go on to the next k.

This technically makes the mathematical case for stopping sieving before sieving is removing n's as fast as LLR searches them but calculating that would become very complex quickly. I've been sieving until it is removing them as fast as they LLR but I would guess optimum in an effort like this is closer to 80-90% as fast.

Also, you reserved the k's. There's no problem with you taking them above n=100K yourself and just getting that portion of the big sieved file from me or whomever is helping with sieving. By the time you get to n=100K, it's likely we'd be close to having sieved them far enough.

This sieve is intended for both personal use by anyone who wants it and for a team drive, which will benefit everyone as a whole. For that matter, if a majority of people are against a team drive, then I'll just post the big sieved file and people can reserve k's individually and search them using the applicable portion of the file.

Flexibility with everyone's resources and tastes is the key in this and any prime-searching effort.


Last fiddled with by gd_barnes on 2007-12-21 at 23:51
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