News - Page 5

TimSorbet · 2008-05-08, 22:53

312,988 digits. equiv. to ~2^1035000. Congrats!

rogue · 2008-05-08, 22:58

Quote:

Originally Posted by gd_barnes

You must have had some serious firepower going after that one. I only showed you at n=200K as of April 24th!

I split the range over a few CPUs. I started one at n=300000 on Monday and the PRP was found later that day. Apparently PFGW is having a problem with the proof. I'm getting the error "Unknown error in PFGW runtime. Possibly a number too big for alloca version of GMP". I had to start the proof on an older version.

BTW, all base 28 k (Sierpinski) are tested to n = 100,000. I made a mistake and did not test the base 28 Riesels. You can unreserve them. I will reserve the Sierpinski and Riesel base 27 k.

rogue · 2008-05-09, 01:40

958*11^300544+1 has been verified as prime by PFGW.

gd_barnes · 2008-05-09, 04:08

Quote:

Originally Posted by rogue

958*11^300544+1 has been verified as prime by PFGW.

AMAZING and congrats again on a monster prime!!

I believe this will move CRUS into 12th place on primes found (from 14th) and move it into 18th place on score (from 20th). I just now looked and the score on it is 33.11! Whew! :-)

BTW, what was your optimal sieve depth for this? It must have been very high although I don't know what its weight is.

Gary

gd_barnes · 2008-05-09, 04:55

One more interesting note on Rogue's Sierp base 11 proof: With a conjectured value of k=1490, it is the highest conjecture that has been proven to date for either side by any project. The previous highest was Sierp base 21 at k=1002.

The next challenge: What's the highest conjecture that we only have ONE k remaining on? By far, it is Sierp base 10 with a conjecture of k=9175. It has only k=7666 remaining at n=195K.

Anyone care to tackle Sierp base 10?

Gary

rogue · 2008-05-09, 12:22

Quote:

Originally Posted by gd_barnes

AMAZING and congrats again on a monster prime!!

I believe this will move CRUS into 12th place on primes found (from 14th) and move it into 18th place on score (from 20th). I just now looked and the score on it is 33.11! Whew! :-)

BTW, what was your optimal sieve depth for this? It must have been very high although I don't know what its weight is.

Gary

I had sieved to 4e12 and was on my way to sieving to 1e13. I was sieving on
one computer and doing PRP testing on 3 others.

gd_barnes · 2008-05-09, 21:30

Quote:

Originally Posted by rogue

I had sieved to 4e12 and was on my way to sieving to 1e13. I was sieving on
one computer and doing PRP testing on 3 others.

Very good. One more question: How long did it take Phrot to find the probable prime? I'd be curious to compare it to LLR or PFGW for probable prime testing.

Gary

rogue · 2008-05-09, 21:52

Quote:

Originally Posted by gd_barnes

Very good. One more question: How long did it take Phrot to find the probable prime? I'd be curious to compare it to LLR or PFGW for probable prime testing.

Gary

On a PowerPC G5 at 2.5 Ghz, it took 9900 seconds (as from my original post on the subject). The verification took 7900 seconds on a 2.4 Ghz Core 2 Duo. I was rather surprised by that because I expected verification to take longer as verification of primes in other bases has taken much longer.

gd_barnes · 2008-07-12, 08:28

I have added links to sieved files for Riesel and Sierp bases 22 and 23 (4 bases total) to the reservations web pages. 3 of the 4 files are sieved past P=5T and the other at P=~3.5T.

The files go from n=100K-1M on most of the k's. The P=5T files should be nearly sufficiently sieved if you plan on testing to only n=200K. Past that, they'll need more sieving. Warning: Taking any of these bases to only n=200K is a large amount of work unless you find primes quickly.

Thanks for the excellent sieving KEP!

Gary

KEP · 2008-07-12, 09:18

Quote:

Originally Posted by gd_barnes

I have added links to sieved files for Riesel and Sierp bases 22 and 23 (4 bases total) to the reservations web pages. 3 of the 4 files are sieved past P=5T and the other at P=~3.5T.

The files go from n=100K-1M on most of the k's. The P=5T files should be nearly sufficiently sieved if you plan on testing to only n=200K. Past that, they'll need more sieving. Warning: Taking any of these bases to only n=200K is a large amount of work unless you find primes quickly.

Thanks for the excellent sieving KEP!

Gary

Your very welcome. The Sierp Base 19 has just been sent to you. With ~3.6 million pairs left to test. Sieve demand using sr2sieve is ~640MB of RAM. I'm going to start soon on working the huge log files for n<=500 for Riesel Base 3, after that I'll send you on e-mail all the PRPs found, before sieving them to n<=25000.

Regards

KEP

gd_barnes · 2008-07-28, 07:44

Come check out the new mini drive for Sierp base 3 here!

2008-07-12, 08:28	#53
gd_barnes "Gary" May 2007 Overland Park, KS 12176₁₀ Posts	I have added links to sieved files for Riesel and Sierp bases 22 and 23 (4 bases total) to the reservations web pages. 3 of the 4 files are sieved past P=5T and the other at P=~3.5T. The files go from n=100K-1M on most of the k's. The P=5T files should be nearly sufficiently sieved if you plan on testing to only n=200K. Past that, they'll need more sieving. Warning: Taking any of these bases to only n=200K is a large amount of work unless you find primes quickly. Thanks for the excellent sieving KEP! Gary Last fiddled with by gd_barnes on 2008-07-12 at 08:30

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2008-05-08, 22:53	#45
TimSorbet Account Deleted "Tim Sorbera" Aug 2006 San Antonio, TX USA 11×389 Posts	312,988 digits. equiv. to ~2^1035000. Congrats!

2008-05-09, 01:40	#47
rogue "Mark" Apr 2003 Between here and the 2×23×157 Posts	958*11^300544+1 has been verified as prime by PFGW.

2008-05-09, 04:55	#49
gd_barnes "Gary" May 2007 Overland Park, KS 27620₈ Posts	One more interesting note on Rogue's Sierp base 11 proof: With a conjectured value of k=1490, it is the highest conjecture that has been proven to date for either side by any project. The previous highest was Sierp base 21 at k=1002. The next challenge: What's the highest conjecture that we only have ONE k remaining on? By far, it is Sierp base 10 with a conjecture of k=9175. It has only k=7666 remaining at n=195K. Anyone care to tackle Sierp base 10? Gary

2008-07-28, 07:44	#55
gd_barnes "Gary" May 2007 Overland Park, KS 27620₈ Posts	Come check out the new mini drive for Sierp base 3 here!