CADO produced nothing better. I *just* got GPU-msieve configured on my linux box, so I'm running a day of my own poly select under msieve. That also means I return to contributing polynomials to this thread, rather than requesting them!

Hello,

at the moment I try to factor this c153:

[code]200342680339792084251385520743186501215219346823549163194073828377349727332880101003701005574557437974308702796632658776489876756467616443528718745464543[/code]which comes from aliquot sequence 30450:817.

No success when running 4k @ 5e7.

Maybe anyone spends time in finding a polynomial for this number?

Thank you in advance.

Alfred-
Welcome to the thread. There are 3 or 4 of us who do this as a service to the forum, and often more than one of us takes a crack at posted numbers. If one person routinely finds better polys, we can maybe learn from their settings choices to improve everyone's poly-select efforts.

I'll give it a run later today, starting from A1 = 8M. Some of the other contributors start from very low A1 values, so my choice reduces the chance of overlapping with their efforts.

I'll also run it, starting from the lowest A1 and just letting it run overnight.

Alfred's C153:
[code]R0 -119250328621427462814050753119
R1 14654358171672929
A0 48009038017914841372960397591214720
A1 2883114358419791404966465065328
A2 2215585683020452198802724
A3 -14246497239281505380
A4 -3176954121545
A5 8307600
skew 727321.52, size 7.365e-15, alpha -6.756, combined = 3.660e-12 rroots = 5[/code]
30 GPU hours, over 500 hits of 4.5e19 or better. Under an hour to run root-opt on the 550ish candidates.

A relatively large request
 

Would anyone like to throw some GPU or cluster time at the 198-digit number

[code]
1470995008670190114384681297661281497403921528899340398996090363664288
2719320287726116626011835604058588986028438939085909646799598805980864
2787777311962112899089139655509778879366789264829227286733
[/code]

which is a Euclid-Mullin number and should be a tractable but large challenge for NFS@home.

I am running (in reasonably-sized slices on a GTX970)
[code]
msieve -nps stage1_norm=1e29 1,15000000
[/code]

which I expect will take a month or so (1e7 .. 1e7+1e5 took 4.5 hours to give ~300,000 candidates, from which root optimisation produced a reasonable number of polynomials with an E-score greater than 4.5e-15). If anyone wants to try different software or different parameters, no time like the present!

I would prefer to have a few dozen candidate polynomials per person rather than just one best-Murphy-E since I've found that best-Murphy-E doesn't tend to win out after trial sieving ... probably pastebin is a good way to distribute such things.

@ VBCurtis

Thank you very much.

[QUOTE]30 GPU hours, over 500 hits of 4.5e19 or better. Under an hour to run root-opt on the 550ish candidates.[/QUOTE]

Once more I still have a few questions.
It is very likely that these questions are answered already for many times, but I do not know the answers.
Be patient please.


1) Is this the time for
"msieve ... -np1 bound1,bound2"
which produces the .m file and
"msieve ... -nps "stage1_norm=limit1, stage2_norm=limit2" which produces the .ms file
or the time for "msieve ... -np1 bound1,bound2" only?

2) Under one hour means the time for "mieve ... -npr" which produces the .p file?

[These two questions in order to compare my "method" of finding a polynomial with yours. ]

3) 500 hits of 4.5e19 or better.
Comes 4.5e19 from the last entry per line?
I suppose better means eg 4.6e19 and not 4.4e19?

4) What is the special meaning of the value 4.5e19 ?

Alfred's C153:

[CODE]
n: 200342680339792084251385520743186501215219346823549163194073828377349727332880101003701005574557437974308702796632658776489876756467616443528718745464543
# norm 9.635214e-15 alpha -5.731471 e 3.859e-12 rroots 5
skew: 9910102.29
c0: 32499064344333747693836052278767798335
c1: 3126905685798081746601052320840
c2: -5075345682477287373503043
c3: 90439175992181516
c4: 59077950604
c5: 420
Y0: -862373527665808095417346348354
Y1: 665033345874870149
[/CODE]

This poly was found after less than 24 CPU hours. It sieves better than the poly of VBCurtis.
The best score was 3.860e-12, but the poly sieved a little bit worse.

I think, that a c153 is too small for GPU polysearch.

[QUOTE=Alfred;418797]@ VBCurtis

1) Is this the time for
"msieve ... -np1 bound1,bound2"
which produces the .m file and
"msieve ... -nps "stage1_norm=limit1, stage2_norm=limit2" which produces the .ms file
or the time for "msieve ... -np1 bound1,bound2" only?

2) Under one hour means the time for "mieve ... -npr" which produces the .p file?

[These two questions in order to compare my "method" of finding a polynomial with yours. ]

3) 500 hits of 4.5e19 or better.
Comes 4.5e19 from the last entry per line?
I suppose better means eg 4.6e19 and not 4.4e19?

4) What is the special meaning of the value 4.5e19 ?[/QUOTE]

1) I run -np1 -nps together, such that msieve only outputs a .ms file.
2) yes.
3) lower is better, for the last entry of each line in the .ms file.
4) Arbitrary; I aim for ~200 hits per day from the -np1 -nps, and got almost 3 times as many as I guessed I would get. Root-opt didn't take long; if root-opt would have taken hours, I would have truncated the file to 200ish candidates (3e19 or maybe even lower). My best hits were in the 8e18 range.

[QUOTE=VBCurtis;418807]1) I run -np1 -nps together, such that msieve only outputs a .ms file.
2) yes.
3) lower is better, for the last entry of each line in the .ms file.
4) Arbitrary; I aim for ~200 hits per day from the -np1 -nps, and got almost 3 times as many as I guessed I would get. Root-opt didn't take long; if root-opt would have taken hours, I would have truncated the file to 200ish candidates (3e19 or maybe even lower). My best hits were in the 8e18 range.[/QUOTE]

Um? Higher Murphy e is better, not worse. And your Es are 6 orders of magnitude less than Gimarel's. I'm very confused at the moment.

I presume he's talking about the stage-2 score (the thing printed at the end of each line in msieve.dat.ms), which is a number of the order 3e+19.

You seem to have confused it with the Murphy scores, which are of the order 3e-12 (so forty-one orders of magnitude different, which I would have expected to make them hard to confuse). The Murphy scores are roughly a probability that a value of the polynomial is sufficiently smooth; I'm not exactly sure what the stage-2 score measures.