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Old 2008-03-25, 16:24   #1
A Sunny Moo
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Aug 2007

624910 Posts
Smile Doublecheck drive #1: k=3-1001 n=100K-260K

Hi all,

This drive will be run similarly to the first-pass team drives except for a few key differences. First of all, these numbers have already been crunched before, so we will probably find relatively few new primes (because the only primes we will find are ones that were missed the first time around). However, in previous doublechecking efforts for the 300<k<=1001 range, there was a somewhat substantial error rate, so I can practically guarantee that we will find some errors.

Secondly, due to the large number of k's (500 total!), and for the sake of easier checking with first-pass results, we are doing reservations for this drive by k, rather than by n as is normally done in the first-pass drives.

NEW NOTE as of 2010/02/27: We will be posting files with 5 k's in each of them sorted by k-value for the entire range of n=100K-260K. Feel free to reserve as few or as many k's as you wish at a time and pull the applicable portion out of the posted sieved files.

Third, we have to limit this drive exclusively to machines that we are extremely confident in the stability of. If your machine is overclocked, it is required that you run a Prime95/mprime stress test on your machine for at least a few hours to ensure that your machine will produce good results. It is also recommended for non-overclocked machines, though for non-overclocked machines, if you are reasonably confident in your system's stability, and you've run some other form of stability confirmation (such as a GIMPS self-test before doing an exponent, or a few GIMPS, SoB, or PrimeGrid BOINC doublecheck numbers successfully completed without error on your machine's part), you can skip the stress test if you want.

The stringent entry requirements are needed because we don't have any first-pass residuals to compare with (as contrasted with the doublecheck projects mentioned in the previous paragraph), and thus we have no way of checking whether the residuals match--we only have primes found to compare. Thus, we need to have the utmost quality of results for this effort. In future doublechecking efforts, such a requirement will not be needed because we will already have residuals to compare with.

We will have reservations available for the 3-300 and 300-1001 ranges of k separately, for the purpose of variety. The higher k's take slightly longer to test, though there isn't that much difference.

It is not explicitly required that the lowest available k-values be tested due to the varying weights of each k. Although we would ask that the reservations be kept as close to the lowest available k-value as possible.

Below are files available for testing. Feel free to take one k at a time.
This drive is complete--thanks to all who participated! Please see the k<300, n=260K-500K extension where you can find plenty more work of similar nature if you are so inclined.

Reserved and available ranges:
3<=k<300 [COMPLETE]
  k       reserved by    status
3-13      Mini-Geek      complete
15-19     Flatlander     complete
21-25     kar_bon        complete
27-31     gd_barnes      complete
33        Flatlander     complete
35        Harvey563      complete
37        Flatlander     complete
39-43     gd_barnes      complete
45-49     Harvey563      complete
51-55     gd_barnes      complete
57-61     Harvey563      complete
63-75     gd_barnes      complete
77-81     Harvey563      complete
83-89     gd_barnes      complete
91-111    Harvey563      complete
113       Flatlander     complete
115-159   Harvey563      complete
161-163   grobie         complete
165-177   gd_barnes      complete
179       grobie         complete
181-299   gd_barnes      complete
  k       reserved by    status
301-307   MyDogBuster    complete
309-311   mdettweiler    complete
313       MooooMoo       complete
315-321   mdettweiler    complete
323-333   Flatlander     complete
335-343   mdettweiler    complete
345-399   gd_barnes      complete
401-405   mdettweiler    complete
407-417   gd_barnes      complete
419-423   mdettweiler    complete
425-499   gd_barnes      complete
501-599   Flatlander     complete
601-699   Sloth          complete
701-799   gd_barnes      complete
801-849   Flatlander     complete
851-1001  Sloth          complete
The following k's <300 have also been double-checked for n=260K-500K. If you would like a sieve file for one or more k's, please email me at (Note: doublechecking of k=300-1001 for n>260K will be handled separately, as for those we have first-pass residuals on file from NPLB's testing of that range.)

  k       reserved by     status
5-15      Harvey563      complete
17        available
19-29     Harvey563      complete
31        gd_barnes      complete
33-299    available
Missing and incorrect primes found:
prime              comments
27*2^282700-1      missing from
29*2^347896-1      missing from
405*2^104462-1     missing from Primesearch
405*2^109496-1     missing from Primesearch
405*2^193516-1     missing from Primesearch
437*2^138124-1     missing from
695*2^103822-1     missing from
713*2^111226-1     missing from
939*2^149765-1     missing from
Please put both primes.log (or whatever you told LLR to use as an output file) and lresults.txt in a zip file at the end of your range and attach the zip file to your post when you report a range as complete. If your results files are too big to attach here, you can email them to me at, though I'd rather if results were attached here whenever possible.

Let's have fun and plow through those doublechecks!

Last fiddled with by mdettweiler on 2012-02-22 at 15:34 Reason: hmm, caught a reference to the old Riesel Sieve project...that hadn't been updated in a while :-)
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