20080215, 22:36  #1 
May 2007
Kansas; USA
7^{2}×211 Posts 
k's/nranges not searched for team drives
Here is a list of k's and nranges for 400<k<=1001 and n=260K600K that we are partially testing or not testing at all for team drives 1, 2, and 3 that were originally reserved by VBCurtis at RPS:
Code:
range range tested kvalue included excluded to n= 343 500K600K 260K500K 600K 359 500K600K 260K500K 600K 361 500K600K 260K500K 600K 375 500K600K 260K500K 600K 415 (none) 260K600K 600K 439 500K600K 260K500K 600K 443 500K600K 260K500K 1.04M 449 500K600K 260K500K 600K 457 500K600K 260K500K 600K 479 500K600K 260K500K 600K 505 500K600K 260K500K 600K All k's and nranges for k<1000 will be included in future doublechecking efforts. Gary Last fiddled with by gd_barnes on 20081226 at 08:11 Reason: update testing ranges 
20080527, 05:58  #2 
"Curtis"
Feb 2005
Riverside, CA
11174_{8} Posts 
Steven (sjtjung) and I paused our 9 k's for a couple months at 400k, but have resumed. I expect we'll complete the 9 k's to 500k and release them by the end of June. As Gary has done with his k<100 reservations, I welcome anyone to continue the searches at 500kup.
Note this applies to any k in 300600 reserved to me except k=443 (edit and 415). I have 443 to 825k now, with a sieve to 3M and no plans to release until I find a CRUS prime for base 16. It will have one or two cores assigned to it for the foreseeable future. Edit I forgot about k=415. I have that one sieved to 1M, but the file has been idle for a long time. I'll assign this one to a machine to catch it up to your drives tomorrow. Sorry! (Not sure where to report my progress this thread looks best.) Curtis Last fiddled with by VBCurtis on 20080527 at 06:04 
20080527, 06:20  #3  
May 2007
Kansas; USA
7^{2}·211 Posts 
Quote:
You might be searching k=443 into the 10million digit range before finding a base 16 prime! Finding another base 2 prime will be difficult enough...base 16 almost impossible. Good luck and thanks for the udpate! Gary 

20080601, 07:03  #4 
"Curtis"
Feb 2005
Riverside, CA
2^{2}·7·13^{2} Posts 
I have a sieve for 415 starting at 260k. However, your pages list 415 as tested to 340k already. Since 340k is roughly the cutoff for top 5000 listing anyway, I started testing there. Is that OK? I think when I reserved it, it was only tested to 260k. I may have tested it to 340 and misplaced the results, or your doublechecks may have already pushed the test limit to 340.
Let me know if I should run the 260340 range to generate results files for your records, or if you already have them. I agree that 443 may be stubborn for a base16 prime. I like searching the lowerweight k's, and the idea of having a reason to test one to high n suits me. I suppose around 2M I'll have to decide whether to start another sieve from 3M up or give up.. but that won't be necessary until fall. Base 16 should merely be 1/8 as likely as base 2, right? Am I right assuming absent detailed info about specific n's that survive the sieve that half of discovered base 2 primes can be expressed as base 4? That's just saying half are even powers, half odd, right? I hope that logic can be extended to base 16. If so, I "merely" have to find 8 primes to expect 1 base 16 prime. Curtis 
20080601, 09:00  #5  
May 2007
Kansas; USA
24143_{8} Posts 
Quote:
Curtis, On k=415, Karsten reflects the highest contiguous nrange that is shown as searched at Primesearch or the nrange that we have completed through, whichever is higher. For k=415, we aren't testing that one so he got the n=340K from the Primesearch site. There, on 1/17/2008, you showed that you completed the ranges from n=260K340K. We're asking that people forward results files for their personal ranges if possible to help in future double checking. So if you can find those, please forward them to us. If not, it's your call as to what you do. On k=443, no, it's not as bad as you think for base 16. 1 out of every FOUR base 2 primes should be a base 16 prime, i.e. 2^4 = 16^1, 2^8 = 16^2, etc. That said, as you probably know, that doesn't mean that the respective weights for base 2 where n==(0 mod 4), n==(2 mod 4), etc. are equal in the long run. Just like there can be 10% even nvalue and 90% odd nvalue primes for a base 2 kvalue, resulting in only 10% as many total base 4 primes as there are total base 2 primes, there can be an extremely uneven distribution of the various modulos for base 16 primes vs. base 2 primes due to unusual distributions of factors, which is clearly the case here. So, no, just because every 4th nvalue makes a base 2 prime a base 16 prime doesn't mean that 1 out of every 4 base 2 primes should be a base 16 prime. It may be more like 1 in 20 or 1 in 100 in the long run!! That is why I think you may be searching into 10Mdigit range for a base 16 prime. Other powersof2 bases kvalues have widely varying weights just like base 2 and they can be very much unrelated to the weight of the base 2 kvalue. It all depends on how the distribution of the factors plays out. Here, since the k is not divisible by 3, all of the base 2 primes must even nvalues. But what is unusual is that they are all n==(2 mod 4), which of course means that while they are all base 4 primes, NONE of them are base 16 primes where n must be divisible by 4. This tells me that while k=443 base 2 and base 4 are very low weight, k=443 base 16 is FAR less than half the weight of base 4. This happens for the same reason that you can get 90% even nvalue and 10% odd nvalue primes on some base 2 k's even though the k is divisible by 3. But one thing you may not have noticed way back in one of the CRUS forum threads is that I alluded to the fact that k=7088 is remaining for Riesel base 256 and that converts to k=443 base 2. As you thought for base 16, THAT is the one that will occur only 1 out of every 8 nvalues! (1 out of every 4 EVEN nvalues in this case.) The bottom line is that to knock out base 16, your prime would need to be n==(0 mod 4) and to knock out base 256, it would need to be n==(4 mod 8). Good luck on that base 256 prime! I would be amazed if we found one in our lifetime! Gary Last fiddled with by gd_barnes on 20080614 at 01:05 

20080704, 08:16  #6 
"Curtis"
Feb 2005
Riverside, CA
2^{2}·7·13^{2} Posts 
415 was completed in a few days to 410k, followed by a nasty crash on that machine rendering it useless. 410 to 500 should run in July when another machine opens up, sooner if our IT
I located the results file for 260340, and plan to send it when I complete to 500k. The machine running 443 also crashed terribly, and I just put that file on a new machine at 825k. A month's work was lost in the crash, roughly. These two were public machines used by undergrads in my dept, and fell victim to viral maladies. The results I do have are legit these weren't hardwarerelated crashes, just impetuous undergrads. Edit: The other 9 k's are complete to roughly 400k, running on one core with a second to be added shortly. I estimate 4 to 8 weeks for completion. These were set aside for a large attack on k=5 and 31 for a few months. Curtis Last fiddled with by VBCurtis on 20080704 at 08:19 Reason: forgot the other 9 k's 
20080720, 08:28  #7 
"Curtis"
Feb 2005
Riverside, CA
2^{2}·7·13^{2} Posts 
415 is active now, complete to 430k. I should be at 500k by the end of July.
The other k's reserved to me are complete to 440k, active on one core at the moment. Steven (sjtjung) is finishing that drive, and will put a second machine on it to get our effort done within 45 weeks. Sorry for the delays. Curtis 
20080720, 09:55  #8  
May 2007
Kansas; USA
7^{2}×211 Posts 
Quote:
First; we have you reserved for k=415 up to n=600K. Is it still your intent to take it that far? If not, we'll do a "sideeffort" search for n=500K600K since we're already nearing n=510K on all k's. Second; can you check your results files and see if you've missed reporting any top5000 or smaller primes? The only one with top5000 primes is k=479 and k=457 had a nontop 5000 prime. It seems very unusual that only 2 of 11 k's would have any primes for the wide range of n=260K to 430K or 440K even considering that a majority are lowweights in your search. Perhaps you've reported them at RPS or elsewhere. I haven't seen in any additional primes reported here or at the Primesearch site. I mention this because we have already found 2 primes for k=375 for n=500K~530K. Thanks, Gary Last fiddled with by gd_barnes on 20080724 at 07:19 

20080724, 07:11  #9 
May 2007
Kansas; USA
7^{2}×211 Posts 
Karsten,
The nranges complete on Curtis's reserved k's should only reflect what he has completed in his minidrive shown in the first post of this thread. On rieselprime.org, you are showing them completed as far as our drives have completed most of the k's. Technically, for the k's he is only searching to n=500K, there is a gap from his search limit up to n=500K. For n>500K, we are including them in our searches. k=375 is the best example where we have found 2 new primes for n>500K but have not searched n<=500K. Gary 
20080724, 12:59  #10 
Mar 2006
Germany
43×67 Posts 
ok, corrected!
PS: not yet. got no connection to the server! perhaps tomorrow! Last fiddled with by kar_bon on 20080724 at 14:30 Reason: PS 
20080724, 14:33  #11 
"Curtis"
Feb 2005
Riverside, CA
2^{2}·7·13^{2} Posts 
Gary
I have 415 sieved to 1M, and plan to take it that far. I have no reason to think there are any unreported primes what incentive would I have to not report something? I've never had LLR fail to print a found prime to primes.txt, but you'll get the results files when my minidrive is done anyway, and can look them over and continue to be surprised. Curtis 
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