20030927, 10:10  #1 
Sep 2003
13×199 Posts 
Exponents that haven't had a P1 test done
First column is Meg range (for instance, 6 = 6,000,000  6,999,999).
Second column is the number of exponents in that range for which 2 matching LL tests were done with no P1 factoring ever having been done for that exponent. Code:
0 0 1 0 2 15152 3 24580 4 18831 5 9243 6 4170 7 1916 8 1454 9 2754 10 140 11 23 12 8 13 6 14 2 15 8 16 3 17 2 18 3 19 1 At low ranges (2M  4M), there's a lot. That's because P1 wasn't added to Prime95 until fairly recent versions, so old exponents got two LL doublechecks done and that was all. At very low ranges (0M  1M) however, the number drops to zero, because someone is systematically P1 trialfactoring all those old small exponents and they've gotten up to about 2.4M. At higher ranges (5M  8M) the numbers drop steadily because P1 factoring got added to Prime95 and the chances are reasonable that at least one of the two computers involved had enough memory to do a P1 test. Still, thousands of exponents never got a P1 test done. Finally at the highest ranges (10M +) the numbers are low because most exponents simply haven't been doublechecked yet. The leading edge of doublechecking is currently sweeping past 10.2M. If every single exponent got a P1 test before a second LL test was performed, those numbers would stay permanently low and a few dozen new factors would be found in each Meg range, assuming a 3% or so chance of finding a P1 factor. I'm not sure why the count picks up sharply in the 9M range after steadily declining. Any ideas? Last fiddled with by GP2 on 20030927 at 10:11 
20030927, 10:15  #2  
"Mike"
Aug 2002
1F5C_{16} Posts 
Quote:


20030927, 10:25  #3 
Sep 2003
A1B_{16} Posts 
First column is Meg range (for instance, 6 = 6,000,000  6,999,999).
Second column is the number of exponents in that range for which at least one LL test was done, but not 2 matching LL tests, and with no P1 factoring ever having been done for that exponent. Code:
0 0 1 0 2 0 3 0 4 0 5 0 6 0 7 2 8 79 9 1507 10 9118 11 5972 12 4122 13 1880 14 1187 15 1062 16 1044 17 1054 18 1053 19 1069 At low ranges (0M  7M), just about every exponent has been doublechecked, so the numbers are zero. The numbers then rise sharply, peaking at 10M (not sure why). Of course, many of the machines that perform the doublechecks will have enough memory to do a P1 trialfactoring before going ahead with the LL doublecheck. But judging by past history some won't, and some thousands of exponents will never get a P1 test done. From 15M19M the numbers decline to a plateau. I'm not sure why. Maybe it's because only modern machines are fast enough to exponents in that range, and such machines are more likely to have plenty of memory (required for P1 testing) and also more likely to have a recent version of Prime95 installed (since P1 trialfactoring was only introduced in fairly recent version of Prime95). If P1 testing could be organized to get through the hump between 10M13M, then after that it would be fairly easy to ensure that P1 trialfactoring always kept ahead of the leading edge of doublechecking (in the "plateau" region). 
20030927, 10:36  #4  
Sep 2003
5033_{8} Posts 
Re: Re: Exponents that haven't had a P1 test done
Quote:
Instead of working through the old exponents, though, it would benefit GIMPS more to do P1 testing just ahead of the leading edge of doublechecking, because this can save redundant LL doublechecks by lowmemory machines. If this we can keep ahead of the leading edge of doublechecking, then no exponent will ever again have 2 LL tests done with no P1 test having been done. As mentioned in my previous message, there's a smooth plateau at 14M+ where it will be very easy to ensure that P1 trialfactoring keeps ahead of the leading edge of doublechecking. But there's a fairly big hump at 1011M, which it would be useful to tackle. Once past that, there's plenty of leisure opportunity to systematically do the 2M range once again. 

20030927, 10:39  #5  
"Mike"
Aug 2002
1F5C_{16} Posts 
Quote:


20030927, 16:50  #6 
"Sander"
Oct 2002
52.345322,5.52471
29×41 Posts 
How can i get a list of exponents that haven't had any p1 testing at all?
As long as it doesn't interfere with primenet it could be a side project of the LMH BTW, a lot of the exponents that have had P1 have verry low bounds which have a very low chance of finding a factor. 
20030927, 17:44  #7  
Aug 2002
Richland, WA
2^{2}×3×11 Posts 
Quote:
If the 9M range had not been mostly doublechecked already, it would have even more exponents without P1 than 10M because most of the 9M exponents were already handed out before the P1 capable client was available. 

20030927, 18:10  #8  
Aug 2002
Richland, WA
2^{2}·3·11 Posts 
Re: Exponents that haven't had a P1 test done
Quote:
Being currently the third highest LL (doublechecks and firsttime tests) producer (see http://www.teamprimerib.com/rr1/topover.htm), with almost all of his computing power focused on doublechecks, he ends up doing a sizable percentage of the doublechecks that are completed. I've noticed that his computers don't seem to do P1 very often, which probably means he has intentionally turned it off because it doesn't give credit proportional to the amount of work done. So, I think the larger number of exponents in the 9M's without P1 is due TempleUCAS not doing P1 while completing a sizable percentage of the doublechecks. He will probably have a similar effect on the 10M range (though it won't be noticable compared to the 9M range). 

20030927, 19:28  #9  
Aug 2002
Richland, WA
2^{2}·3·11 Posts 
Re: Re: Exponents that haven't had a P1 test done
Quote:


20030927, 20:07  #10  
Sep 2003
13×199 Posts 
Quote:
If you want to try do P1 trialfactoring just ahead of the leading edge of doublechecking, see the Marin's Mersennearies forum. If you want some other range, let me know. I could also come up with a list of P1 test with very low bounds. 

20030927, 20:32  #11 
Aug 2002
Texas
10011011_{2} Posts 
Another suggestion for those interested in and who have the means to P1 test exponents would be to use PrimeNet to request a block of DC's and turn the sequentalwork switch on in prime.ini. It will go through and P1 the exponents that need it and return the result to the server. When the batch is done just unreserve the lot, wait a while for them to be assigned to others and repeat. Has worked for me in the past when I wanted to get some coveted double check factors, plus clears the way for the generally older DC machines to concentrate on LL iterations.
Gratuitous dancing 
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