Sierp base 63 - team drive #5

[rogue]

I had this group spread across four cores. It finished overnight. I have revised my estimate for the time needed for a single group to about three months on a single core of a Core 2 Duo at 2.4 GHz. The results are attached. I ask that everyone add the group name to their files before you submit your results.

Here is a summary:

7036 starting k
5338 primes found
1698 k remaining

This removed about 75.87% of the ks. I estimate that once all k reach n=10000 that there will be about 57,204 k remaining.

[Mini-Geek]

Originally Posted by rogue

I had this group spread across four cores. It finished overnight. I have revised my estimate for the time needed for a single group to about three months on a single core of a Core 2 Duo at 2.4 GHz. The results are attached. I ask that everyone add the group name to their files before you submit your results.

Maybe I'm misunderstanding something, but what quad can run about 2 C2D-2.4GHz months (7036/10000 * 3 months) overnight? Each core would need to run equivalent to about a 432 GHz C2D core (there's 1440 hours in 60 days, figuring 8 hours is "overnight", that's 1440/8=180 times faster; 180*2.4=432). I know this is probably excluding sieving, which is probably significant, but optimal sieving is (almost?) always much shorter than the test, so it shouldn't affect that too significantly.
On rereading, did you mean that it finished overnight but was started some time ago? I took it to mean that it ran and finished overnight. How long did it take 4 cores to complete your group? How long did the sieving take?

[rogue]

Originally Posted by Mini-Geek

Maybe I'm misunderstanding something, but what quad can run about 2 C2D-2.4GHz months (7036/10000 * 3 months) overnight? Each core would need to run equivalent to about a 432 GHz C2D core (there's 1440 hours in 60 days, figuring 8 hours is "overnight", that's 1440/8=180 times faster; 180*2.4=432). I know this is probably excluding sieving, which is probably significant, but optimal sieving is (almost?) always much shorter than the test, so it shouldn't affect that too significantly.
On rereading, did you mean that it finished overnight but was started some time ago? I took it to mean that it ran and finished overnight. How long did it take 4 cores to complete your group? How long did the sieving take?

I started two weeks ago (on the 14th). I split the 7036 k into four files. I sieved each file to about 4e9, which took about 30 hours. Extrapolating that to 2500 per file (from about 1750) implies that sieving should take about 42 hours, although sieving longer (48 hours) probably won't have a significant impact. PRP testing started Friday, about two weeks ago. The cores finished through the week, but at different times because I didn't split exactly at 7036/4. The smallest file took about 12 days and the largest took about 15 days. The smallest file contained a little more than 1400 k, which is about 1/7th of 10,000. This should yield around 84 days, but presuming users might have processes stealing cycles and other potential maintenance, I would extend that to about 90 days. Clearly it could be done in less time, but I would prefer to over-estimate the effort rather than under-estimate it.

[Lennart]

Here are the primes from group02

7670 Primes

Lennart

Edit:
There are 48 k's with 2 primes each and 1 k with 4 primes so there are 7619 k's with primes and 2381 k's remaining for this group.

[gd_barnes]

Originally Posted by Lennart

Here are the primes from group02

7670 Primes

Lennart

Very good and close to Mark's prime percentage...76.7% vs. 75.87%. With that verification, ~57K k's remaining at n=10K as shown by Mark looks like a good estimate.

This is not as "prime" of a base as I had hoped for for a 2^q-1 base. The above estimate would be like 57 k's remaining for a conjecture of k=37K at n=10K. That's good but not great for this size of base. Base 31 is definitely better for its base and conjecture size. It would be like 11 k's remaining for a conjecture of k=64K at n=25K; one of the better ones I've seen. Base 3 has no peer in that regard.

[gd_barnes]

I found another k that is actually remaining at n=1000 but wasn't in the original file of k's remaining. It is k=17131266. Fortunately I was able to eliminate it:

17131266*63^3205+1 is prime

So that now makes 3 k's remaining at n=1000 that weren't in the original file but all of them have primes found for n>1000. That means they don't have to be somehow added to this drive later on.

For my n<=1000 doublecheck, I'm now at k=18M and continuing on until I've finished all k's.

[gd_barnes]

Originally Posted by Lennart

Here are the primes from group02

7670 Primes

Lennart

Lennart,

To save me some time later on, could you forward or post the k's remaining in this group?

Mark,

Since you're administering the effort, if you have an easy way to take the primes from each person and remove them from the k's remaining at n=1K to get the k's remaining at n=10K, then feel free to. If you do that, sending a large continguous range of k's remaining to me after several contiguous groups have been completed would work the best for me; perhaps after groups 1 thru 6 have been completed.


Thanks,
Gary

[rogue]

Originally Posted by gd_barnes

Since you're administering the effort, if you have an easy way to take the primes from each person and remove them from the k's remaining at n=1K to get the k's remaining at n=10K, then feel free to. If you do that, sending a large continguous range of k's remaining to me after several contiguous groups have been completed would work the best for me; perhaps after groups 1 thru 6 have been completed.

That will be easy to do. This is what I do:

1) Take the file I posted and strip everything from '*' and after.
2) Take the file of primes found and do the same.
3) Sort each file by k.
4) diff the two files and redirect to another file.
5) Verify that new file only has added lines in the first file and no added lines in the second file. If this step fails, I need to investigate.
6) Sort the new file and strip out extraneous information.
7) Count the number of line in each file (obviously 1 k per line)
8) If "lines in original" - "primes found" = "lines from diff", then I'm good to go and the output from step 6 is the remaining k for the range.

Most of these things are easy to do with TextPad, except diff. I use the command line diff from CygWin because TextPad diff doesn't work very well. TextPad does have the ability to remove duplicate lines when sorting. I do that with step 3. AFAIAC, if there are two or more primes for one k, then it will eliminate the duplicate k so that each k appears once in the file.

[Lennart]

Sierp 63 G03 done 7582 primes

Edit:
1 k-value had 2 primes so there are 7581 k's with primes and 2419 k's remaining for this group.

The k and primes are:
k=4892176 for n=5812 and 5948

[Lennart]

Sierp 63 G05 done 7636 primes


Lennart

Edit:
1 k-value had 2 primes so there are 7635 k's with primes and 2365 k's remaining for this group.

The k and primes are:
k=8169440 for n=5234 and 5236

[Lennart]

Sierp 63 G04 done 7702 primes

Lennart

Edit:
There are 45 k's with 2 primes each so there are 7657 k's with primes and 2343 k's remaining for this group.