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 Batalov 2012-06-30 04:46

6,447- (snfs difficulty 232) is waiting for a knight in shining armor and a reasonably modern home bread maker or a pressure cooker. I heard that those have ridiculously strong CPUs recently.

Seriously, a good project for a home computer (a month on a quad-core, less on a hexa)! Write to Sam before too late.

 debrouxl 2012-06-30 05:54

SNFS 232 would be in the reach of RSALS, if the polynomial is quintic or sextic; but before I reserve this, I'd like to make some test sieving.
What's the best SNFS polynomial for that number ? :smile:

 Batalov 2012-06-30 06:18

Like,
[CODE]n: 616206951833849099509404360836151448327434546464783674219667801836184526666386100726932863976883607096993792653424911139417437242190871728765383549637572368393220053069548102628443735964624521073
type: snfs
skew: 1.82
Y1: 1
Y0: -808281277464764060643139600456536293376
c6: 1
c3: 6
c0: 36
rlim: 55000000
alim: 55000000
lpbr: 30
lpba: 30
mfbr: 60
mfba: 60
rlambda: 2.6
alambda: 2.6
[/CODE]
but try 3LP on both sides and see if it gets better? (For this size, maybe not.)

 debrouxl 2012-06-30 08:21

On one core of an otherwise idle i7-2670QM, at q=rlim/2, 2LP sieving and 3LP sieving produce the same yield at the same speed (only the fifth digit after the comma changes, which is way below noise). It doesn't hurt to make a 3LP sieving.

I've sent an e-mail to Sam Wagstaff for reserving 6,447-.

 debrouxl 2012-06-30 19:54

BTW, before I queue it to the bread makers, pressure cookers and whatever else composes RSALS: how much ECM has 6,447- received ?
I can't find the information (or at least, it's not obvious to me ^^) through [url]http://homes.cerias.purdue.edu/~ssw/cun/[/url] .

 Batalov 2012-06-30 20:02

Tons. Rest assured.

S.S.W. himself found very large factors in this portion while it was still in the [URL="http://homes.cerias.purdue.edu/~ssw/cun/xtend/"]future extension[/URL] stage.
Also Bouvier recently added many more curves (supposedly with the GPU-GMP-ECM) and found some impressive factors. There's no direct evidence, though; but it has been observed that they ECMd even less snfs-difficult numbers very heavily in the past.

I'd like to reserve the post-processing.

 jrk 2012-06-30 20:48

[QUOTE=debrouxl;303720]It doesn't hurt to make a 3LP sieving.[/QUOTE]
FYI, You might see an increase in the duplication rate, unless you also increase the large prime size.

 Batalov 2013-09-12 04:49

6- tables were officially extended. (from 451 to 500)

There may be some projects accessible to home-style enthusiasts, e.g. 6,471-.

 frmky 2016-08-04 04:24

6,383- is done.

[PASTEBIN]N0hgKLks[/PASTEBIN]

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