msieve143_gpu.exe -np 1200,2400
didn't find polynomials yet, but it only took 9 hrs. I'll try another interval.

Here's a preliminary poly found with Jason's new msieve-gpu branch.

[code]# norm 2.523819e-15 alpha -7.877120 e 1.839e-12
skew: 2785154.52
c0: -138570565461588730821881652221421126805
c1: -356118891405782364779335898545631
c2: 157627527368055796683392529
c3: 368273140050413578367
c4: -24904624740140
c5: 949200
Y0: -1035248474311472807522765292042
Y1: 832063911771386519
[/code]

Note that msieve's final_norm cutoff for this composite is 1.835e-12.

My curvefits suggest > 1.95e-12 would be good.

[QUOTE=bsquared;192729]My curvefits suggest > 1.95e-12 would be good.[/QUOTE]

The previous c157 had a 2.00e-12 poly.

[quote=10metreh;192730]The previous c157 had a 2.00e-12 poly.[/quote]

And it was good :wink:.

[quote=Greebley;192712]I was thinking it would be neat to get 314718 to index 9000, however it is at 8902 now so that would be a long 92 indices more.
It is index 2540 for 4788.[/quote]

[quote]Both those figures are wrong: 314718 is at index 8908, and 4788 is at index 2448.[/quote]

Yeah the index is 8908 which is 92 indices from 9000 so I mis-typed that one.

However, the other value (2540) is the current index + 92 i.e. we could stop at index 2540 for that is when we reach 9000 for 314718. So for that one it just wasn't clear what I was trying to say.

To summarize:
My suggestion is to run the sequence 4788 to index 2540 if we can.

[QUOTE=Greebley;192736]My suggestion is to run the sequence 4788 to index 2540 if we can.[/QUOTE]

Unless we acquire the downdriver at something ridiculous like 172 digits, in which case we just [B]have[/B] to continue. :smile:

I'll run pol51 for 0-200M using following parameters:
[CODE]pol51m0b -b c157_1 -p 7 -n 2.8e23 -a 0 -A 200000
pol51opt -b c157_1 -n 3.6e22 -N 3.6e19 -e 1.7e-12
[/CODE]

I left the range running overnight, and woke up to these:

[code]
polysel_0-2500.cand:BEGIN POLY #skewness 979863.43 norm 8.85e+20 alpha -5.12 Murphy_E 2.14e-12
polysel_0-2500.cand:BEGIN POLY #skewness 1249264.69 norm 1.13e+21 alpha -5.19 Murphy_E 2.07e-12
polysel_0-2500.cand:BEGIN POLY #skewness 1239920.67 norm 1.08e+21 alpha -5.17 Murphy_E 2.07e-12
polysel_0-2500.cand:BEGIN POLY #skewness 1064109.97 norm 9.82e+20 alpha -4.76 Murphy_E 1.97e-12
polysel_0-2500.cand:BEGIN POLY #skewness 979626.75 norm 9.01e+20 alpha -4.60 Murphy_E 1.94e-12
[/code]

I'll let it continue to run... in the mean time, anyone care to test sieve the top 2 or 3? We can probably duplicate the siever and parameters from the last C157.

details:
[code]
n: 1128681916333165583281832717120127496638972860118923964844791402387721331170448754199775637678274646951935918929237315749341487244542351920306209843985409563
#skewness 979863.43 norm 8.85e+20 alpha -5.12 Murphy_E 2.14e-12
c5: 156600
c4: 5511109690356
c3: 2556240664351703353
c2: -2709038327031089573784479
c1: 772591600803924819123938074991
c0: -127641604647397600699119628378829341
Y1: 64393121809011209
Y0: -1484416691862834512911536697536
skew: 197324.88
rlim: 45000000
alim: 45000000
lpbr: 29
lpba: 29
mfbr: 58
mfba: 58
rlambda: 2.6
alambda: 2.6

n: 1128681916333165583281832717120127496638972860118923964844791402387721331170448754199775637678274646951935918929237315749341487244542351920306209843985409563
#skewness 1249264.69 norm 1.13e+21 alpha -5.19 Murphy_E 2.07e-12
c5: 156600
c4: 5314399732356
c3: -2883058196108786471
c2: -2573465483932011297872477
c1: 2271343202342143863498206577119
c0: 23472793401947121132547837819239017
Y1: 64393121809011209
Y0: -1484416708040060932502186689770
skew: 197324.88
rlim: 45000000
alim: 45000000
lpbr: 29
lpba: 29
mfbr: 58
mfba: 58
rlambda: 2.6
alambda: 2.6

n: 1128681916333165583281832717120127496638972860118923964844791402387721331170448754199775637678274646951935918929237315749341487244542351920306209843985409563
#skewness 1239920.67 norm 1.08e+21 alpha -5.17 Murphy_E 2.07e-12
c5: 156600
c4: 5335915006356
c3: -2297759499328129799
c2: -2787019491787729028389067
c1: 2123826836917266179771394505903
c0: 18333066845778520513050090022694295
Y1: 64393121809011209
Y0: -1484416706270666731434176688868
skew: 197324.88
rlim: 45000000
alim: 45000000
lpbr: 29
lpba: 29
mfbr: 58
mfba: 58
rlambda: 2.6
alambda: 2.6
[/code]

I just realized all of those (and a half dozen more 1.9x 's) have the same leading coefficient! Never seen that before...

once i have finally managed to compile msieve-gpu i will have a CUDA gpu i can run on polynomial selection
it is proving difficult to get environment variables and such like correct

all you need is a nvidia series >=8
those look good polys

[quote=bsquared;192797]I left the range running overnight, and woke up to these:

[code]
polysel_0-2500.cand:BEGIN POLY #skewness 979863.43 norm 8.85e+20 alpha -5.12 Murphy_E 2.14e-12
polysel_0-2500.cand:BEGIN POLY #skewness 1249264.69 norm 1.13e+21 alpha -5.19 Murphy_E 2.07e-12
polysel_0-2500.cand:BEGIN POLY #skewness 1239920.67 norm 1.08e+21 alpha -5.17 Murphy_E 2.07e-12
polysel_0-2500.cand:BEGIN POLY #skewness 1064109.97 norm 9.82e+20 alpha -4.76 Murphy_E 1.97e-12
polysel_0-2500.cand:BEGIN POLY #skewness 979626.75 norm 9.01e+20 alpha -4.60 Murphy_E 1.94e-12
[/code]

[/quote]

I decided to do some test sieving on the top 3 as well as jrk's msieve poly. I was dissapointed by the performance of the top poly (about 1100 rels in a range of 1000 Q starting at 10M, 0.170 sec/rel), and the others were even worse in comparison. So on a whim I drug out a 1.92e-12 scoring poly with a better alpha (-6.44), and it beat the pants off of the 2.14e-12 poly. Rough curve fits of test sieving 1k blocks from 5M to 50M in steps of 5M suggest we'll need about 43MQ and about 7 million cpu seconds (based on data from a 3.16 GHz core 2) or 81 CPU days.

I think there are better polys to be found, but this is the baseline so far. Lesson to be learned: Murphy_E is a crapshoot!