Message boards : Project Staging Area : Are PPS sieve results used in k=27 and k=121 projects?

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Myrskylyhty

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Message 116290 - Posted: 22 Mar 2018 | 9:10:17 UTC

Couldn't find info on this:

Since PPS sieve is currently sieving range n=6-9M, will/are those results being used for the k=27 and k=121 PRPNet projects? Their leading edges are at n=6,829,102 and n=7,648,452 respectively for the +1 form.

PPS sieve is a very active project that is also utilizing the GPU very well, so you'd think that it will at some point go deeper than the current/past cpu(?) sieve for 27 and 121.

Thank you :)

JimB
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Message 116291 - Posted: 22 Mar 2018 | 10:48:53 UTC

Yes, of course. PPS9M-12M is sieved to p=20000T and will probably be moving to BOINC (replacing 6M-9M) before k=27 and k=121 need those candidates. It's also possible to sieve just those k's much higher much faster if necessary. Every time I load work on k=27 and k=121, I use (or create) the latest sieve file incorporating all factors more than an hour or so old.

Myrskylyhty

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Message 116292 - Posted: 22 Mar 2018 | 11:18:25 UTC - in response to Message 116291.

Nice!

That means that actually even though other PPS k's will take years to reach that range, we can already utilize some of the extensive sieve work in k=27 and k=121 in PRPNet.

Is there some mathematical reason why 27=3^3 and 121=11^2 have their own PRPNet project and they're not done alongside other PPS searches? Or are they just older projects that have been alive longer than other PPS k projects? (This applies to k=3 too, but for it is separate probably also because its the most efficient PPS k?)

JimB
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Message 116302 - Posted: 22 Mar 2018 | 13:02:53 UTC

They were from an external prime finding effort that merged with PrimeGrid (before my time here). See http://www.primegrid.com/forum_thread.php?id=2414.

Message boards : Project Staging Area : Are PPS sieve results used in k=27 and k=121 projects?