[quote=VBCurtis;121947]Riesel 28:
7367 yielded a prime, noted in primes thread. 6207 complete to 25k, no prime.

Starting 5886 tonight, with the rest of the 5000's to follow. All to 25k. Finding two primes so easily has me fueled to aim for all of Riesel 28 to 25k, but I'll reserve it in chunks in case I get distracted by another new search.

-Curtis[/quote]

OK, thanks. Gotcha down for k=5076, 5133, 5306, and 5886 reserved to n=25K.


Gary

[quote=gd_barnes;122023]Hum...good question. Were you previously implying that you were getting 1000 sec. test time around n=62-63K? I wasn't clear there because my test time for my last test at n=62413 was 447 secs so it sounded a little high.[/quote]
Yes, I did say that I was getting 1000-1200 second test times around n=62-63K. You're right, it does seem a little high...maybe it's just because I need to clean out my CPU fan again. (Also I need to clean out the area behind the computer case so it doesn't suck in so much dust! :smile:)

[quote]It may depend on how fast your machine sieves vs. LLR's. If you have a strong sieving machine, then the answer may be yes. Otherwise maybe not.

The case against sieving further is that you're only LLRing a narrower range of n than that which I originally sieved. When I sieved, (if I remember right) I sieved until the removal rate was about 500-600 secs. on my dual-core Dell laptop because I was sieving the range of n=25K=100K and that was just a little less testing time than I got for the 70% range of around n=77K.

I've started sieving to slightly less than what would normally be the optimal sieve depth for the conjecture efforts due to the fact that if a prime is found, the rest of the file is simply wasted. In this case, I still think the optimum sieve may have been only P=500G, but even that would save little additional testing time. Once you get close to the optimum, it doesn't matter a whole lot whether the time is spent sieving or LLRing.


Gary[/quote]
Okay, I think I'll just continue LLRing. Thanks! :smile:

Update on reserved bases
 

I've finished range is 115*26^n-1 until 100000. I am continuing with the others that I have reserved.

Laters, Willem.

Great post about sieving, Curtis. This is outstanding information! And I thought I was a math nerd! :geek: :grin:

I have moved the discussions about sieving over the sieving thread. I will continue it there.


Thanks,
Gary

i give riesel base 6 a shot:
k=1597: sieved to p=1.5T, 2200 candidates left to n=500k
llr-tested to n=153k, no prime yet

k=9577: sieved to p=186G, 9300 candidates left to n=500k (sieving further)
llr-tested to n=38k, no prime yet

all other 17 k's: sieved to p=11G, sieve-rate 1s, sieving further
274000 candidates to n=1M
no llr-tests yet

Top5000 entry is at n=129k!

karsten

[quote=kar_bon;122164]i give riesel base 6 a shot:
k=1597: sieved to p=1.5T, 2200 candidates left to n=500k
llr-tested to n=153k, no prime yet

k=9577: sieved to p=186G, 9300 candidates left to n=500k (sieving further)
llr-tested to n=38k, no prime yet

all other 17 k's: sieved to p=11G, sieve-rate 1s, sieving further
274000 candidates to n=1M
no llr-tests yet

Top5000 entry is at n=129k!

karsten[/quote]

Great! Welcome to the effort Karsten. That's some major sieving you've done!

Team drive #1 is about to start on Sierp base 16. New thread to follow shortly...


Gary

Now that the team drive is open, I'm releasing Riesel Base 13 k=288 at n=66K. (I was mainly running it to hold me over until the team drive was ready.) I've attached the lresults file, as well as the sieve file for the remaining candidates up to n=100K (so that Gary doesn't have to do the work of splitting off the candidates that I've tested from the sieve file on the web pages).

If I understand the Riesel base 16 effort correctly, I can run the base two sieve and by extension contribute to this effort. If this is right, I'd like to reserve 443 for a regular search (base 2, not 16). I'll report both base 2 and base 16 n-values as I complete them.
I'll test it to 1200k base 2, 300k base 16.
This k is low-weight, so even this large sieve is not likely to find a prime for this k. Even if I do, the prime may not be a prime for base 16 (the power would have to be a multiple of 4 to eliminate the k, right?)
-Curtis

Proving riesel base 31 has become about 5% easier:

918*31^17504-1 is prime.

That leaves 18 candidates

[quote=VBCurtis;122218]If I understand the Riesel base 16 effort correctly, I can run the base two sieve and by extension contribute to this effort. If this is right, I'd like to reserve 443 for a regular search (base 2, not 16). I'll report both base 2 and base 16 n-values as I complete them.
I'll test it to 1200k base 2, 300k base 16.
This k is low-weight, so even this large sieve is not likely to find a prime for this k. Even if I do, the prime may not be a prime for base 16 (the power would have to be a multiple of 4 to eliminate the k, right?)
-Curtis[/quote]

You are correct. The power would have to be a multiple of 4. I show it tested to n=65K on the reservation page because it shows as tested to n=260K on RPS and Prime Search. I'm assuming that you'll start testing from n=260K base 2.

I effectively double-checked it to n=25K base 16 with the effort that Anon and I had to double-check all 300<k<=1001 up to n=100K.

I had previously said that I'll double check k=443, 1478, and 3620 up to n=65K, 65K, and 75K base 16 respectively and I'll stick with doing that after I'm done sieving team drive #2 for Riesel base 16. These are all effectively Prime Search k's and I don't trust their ranges. k=1478 and 3620 convert to k=739 and 905. k=739 must have a prime where n==1 mod 4 base 2 and k=905 must have a prime where n==2 mod 4 base 2 in order for the corresponding base 16 k to have a prime.

I'll get you reserved to n=300K for this k.


Gary

17 k's from riesel base 6
 

here the first prime:

17459*6^25627-1 is prime!

it was the 10th candidate for this k i tested!!!
now about 11400 candidates less to test upto n=1M.