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Old 2019-06-02, 03:07   #727
RichD
 
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Quote:
Originally Posted by ThomRuley View Post
(52379047267^23-1)/(52379047267-1)
This number has been fully ECMed with 20K curves at 260e6. I have no plans doing anything more with it at this time.
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Old 2019-06-02, 12:34   #728
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Quote:
Originally Posted by RichD View Post
This number has been fully ECMed with 20K curves at 260e6. I have no plans doing anything more with it at this time.
Have you done anything with
(7489^67-1)/(7489-1)?

All I can do at the moment is ECM, so if you haven't done anything with the above, I'll take it instead.
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Old 2019-06-02, 12:51   #729
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Quote:
Originally Posted by ThomRuley View Post
Have you done anything with
(7489^67-1)/(7489-1)?

All I can do at the moment is ECM, so if you haven't done anything with the above, I'll take it instead.
No work by me...
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Old 2019-09-17, 09:20   #730
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I'll take 41442572371^19-1 from t800. It seems to be going a little slower than I would have expected, but perhaps I'm out of practice. Unless I'm missing something obvious, this is a simple deg 6 poly right? p*(p^3)^6-1 and skew 1?

ETA is in the 8 - 10 day range.
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Old 2019-09-17, 15:41   #731
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I'd recommend a skew of about 0.017 since c6 is much larger than c0, That should increase yield a bit (but test it).

You should be OK to switch skew part way through a run.

Chris
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Old 2019-09-17, 16:08   #732
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Quote:
Originally Posted by lavalamp View Post
I'll take 41442572371^19-1 from t800. It seems to be going a little slower than I would have expected, but perhaps I'm out of practice. Unless I'm missing something obvious, this is a simple deg 6 poly right? p*(p^3)^6-1 and skew 1?

ETA is in the 8 - 10 day range.
Have you tried the degree 5 & 4 ? (p^4)^5-p and (p^5)^4-p ?

Also, are you sieving on the algebraic side of the degree-6?
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Old 2019-09-17, 17:12   #733
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Quote:
Originally Posted by axn View Post
Have you tried the degree 5 & 4 ? (p^4)^5-p and (p^5)^4-p ?

Also, are you sieving on the algebraic side of the degree-6?

Degree 4 will be much slower at this size of exponent, in my experience. Degree 5 may be worth a look but I think the original polynomial from lavalamp will probably be best.
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Old 2019-09-17, 19:52   #734
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Quote:
Originally Posted by chris2be8 View Post
I'd recommend a skew of about 0.017 since c6 is much larger than c0, That should increase yield a bit (but test it).
Oh yes, that nearly doubled the speed. I had previously thought that skew should be a minimum of 1, but it seems not.

I tried the degree 5, it's somewhat slower and needs more relations.

I'm sieving the algebraic side as it is a little faster.
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Old 2019-09-21, 19:20   #735
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I've had an issue with SNFS and wondering if anyone can shed some light on it. It's happened on two different jobs so far, and the symptoms are exactly the same. This is the log file:
Code:
Thu Sep 19 20:26:04 2019 Found 11742819 relations, 48.3% of the estimated minimum (24306044).
Thu Sep 19 20:26:04 2019 LatSieveTime: 1600.9
Thu Sep 19 20:26:04 2019 -> making sieve job for q = 4000000 in 4000000 .. 4025000 as file test.job.T0
Thu Sep 19 20:26:04 2019 -> making sieve job for q = 4025000 in 4025000 .. 4050000 as file test.job.T1
Thu Sep 19 20:26:04 2019 -> making sieve job for q = 4050000 in 4050000 .. 4075000 as file test.job.T2
Thu Sep 19 20:26:04 2019 -> making sieve job for q = 4075000 in 4075000 .. 4100000 as file test.job.T3
Thu Sep 19 20:26:04 2019 -> Lattice sieving algebraic q from 4000000 to 4100000.
Thu Sep 19 20:26:04 2019 -> gnfs-lasieve4I14e -k -o spairs.out.T0 -v -n 0 -a test.job.T0
Thu Sep 19 20:26:04 2019 -> gnfs-lasieve4I14e -k -o spairs.out.T1 -v -n 1 -a test.job.T1
Thu Sep 19 20:26:04 2019 -> gnfs-lasieve4I14e -k -o spairs.out.T2 -v -n 2 -a test.job.T2
Thu Sep 19 20:26:04 2019 -> gnfs-lasieve4I14e -k -o spairs.out.T3 -v -n 3 -a test.job.T3
Thu Sep 19 20:26:39 2019 -> Return value 3221225477. Updating job file and terminating...
Thu Sep 19 20:26:39 2019 LatSieveTime: 35.0657
Code:
Sat Sep 21 09:28:17 2019 Found 10760363 relations, 42.8% of the estimated minimum (25118864).
Sat Sep 21 09:28:17 2019 LatSieveTime: 1605.97
Sat Sep 21 09:28:17 2019 -> making sieve job for q = 4000000 in 4000000 .. 4025000 as file test.job.T0
Sat Sep 21 09:28:17 2019 -> making sieve job for q = 4025000 in 4025000 .. 4050000 as file test.job.T1
Sat Sep 21 09:28:17 2019 -> making sieve job for q = 4050000 in 4050000 .. 4075000 as file test.job.T2
Sat Sep 21 09:28:17 2019 -> making sieve job for q = 4075000 in 4075000 .. 4100000 as file test.job.T3
Sat Sep 21 09:28:17 2019 -> Lattice sieving algebraic q from 4000000 to 4100000.
Sat Sep 21 09:28:17 2019 -> gnfs-lasieve4I14e -k -o spairs.out.T0 -v -n 0 -a test.job.T0
Sat Sep 21 09:28:17 2019 -> gnfs-lasieve4I14e -k -o spairs.out.T1 -v -n 1 -a test.job.T1
Sat Sep 21 09:28:17 2019 -> gnfs-lasieve4I14e -k -o spairs.out.T2 -v -n 2 -a test.job.T2
Sat Sep 21 09:28:17 2019 -> gnfs-lasieve4I14e -k -o spairs.out.T3 -v -n 3 -a test.job.T3
Sat Sep 21 09:28:20 2019 -> Return value 3221225477. Updating job file and terminating...
Sat Sep 21 09:28:20 2019 LatSieveTime: 3.03377
At this point the script terminates but I don't notice for several hours and later get annoyed that my machine has been idle all this time.

If I manually edit q to skip over the 4M to 4.1M range, the script progresses fine as before. Both jobs failed in exactly the same 4M to 4.1M range, both are 6th degree polynomials for p^7-1.
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Old 2019-09-21, 22:24   #736
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The only tidbit I can offer, if it is p^7-1, then it should be sieved on the rational side.
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Old 2019-09-22, 15:51   #737
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What screen output did you get? That should tell us if the sievers said anything interesting.

What did test.job.T* contain?

How much was written to spairs.out.T* (if one is empty but the rest contain relations that would tell us which thread had the problem)?

What happens if you try to restart sieving the 4M to 4.1M range? That would say if it's a transient error or not. And you would be ready to catch screen output if it fails.

What script are you using?

And what OS version, software version, type of CPU etc?

Chris
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