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 2020-03-22, 13:14 #1772 EdH     "Ed Hall" Dec 2009 Adirondack Mtns 336810 Posts 3+2,620 (GNFS) Code: 30016614534509185538267643811098950235950800577843553215914188199521848201 13314606811334378236794012712692141063589808880388357960397353852726553013022276102779033601
 2020-03-22, 13:21 #1773 EdH     "Ed Hall" Dec 2009 Adirondack Mtns 23×421 Posts 9+2,586M (GNFS) Code: 22892248823338312080292806210051631753143696127735096749122777071527433 40814275681048767532336611399735131346712766890469860126480620490503136016233128328129
 2020-03-23, 06:42 #1774 sparrow   Mar 2020 22 Posts 12 + 3,331? http://factordb.com/index.php?id=1100000001473043132 Code: 12^331+3^331<358> = 3^331 · 5 · 589181 · 432655397 · 51861618869<11> · 1780051652040095043377<22> · 1095236138...33<60> · 1484943149...77<94> Added to database during this request? Attached Thumbnails
2020-03-23, 14:11   #1775
jyb

Aug 2005
Seattle, WA

25·72 Posts

Quote:
 Originally Posted by sparrow http://factordb.com/index.php?id=1100000001473043132 Code: 12^331+3^331<358> = 3^331 · 5 · 589181 · 432655397 · 51861618869<11> · 1780051652040095043377<22> · 1095236138...33<60> · 1484943149...77<94> Added to database during this request?
This number is not a Homogeneous Cunningham number:

12^331 + 3^331 = 3^331(4^331 + 1) = 3^331(2^662 + 1)

So the only part of it which is interesting is 2^662 + 1, which is a standard Cunningham number. It can be found in the 2LM table here.

 2020-03-26, 14:28 #1776 swellman     Jun 2012 2×5×7×41 Posts I presume 8+3_320 (C175) is best factored with GNFS, correct? The quartic SNFS is difficulty 231 which will be slow to sieve I think. Anybody want 9-7_269 (GNFS 167) or should I grab it for NFS@Home?
2020-03-26, 17:07   #1777
EdH

"Ed Hall"
Dec 2009
Adirondack Mtns

23·421 Posts

Quote:
 Originally Posted by swellman I presume 8+3_320 (C175) is best factored with GNFS, correct? The quartic SNFS is difficulty 231 which will be slow to sieve I think. Anybody want 9-7_269 (GNFS 167) or should I grab it for NFS@Home?
I did a couple quartic snfs jobs as gnfs and didn't have too much issue. I'm now running 6+5,370 snfs with a quartic to see how it turns out. 8+3,320 would be on my list, if 6+5,370 works OK, but I don't know how soon that might be. After that, depending on how long it takes and whether something smaller turns up, I would look at 9-7,269.

But all this might be a while and it's dependent on how 6+5,370 finishes. I kind of expect it to move to LA tomorrow, even though CADO-NFS will be checking later today for a "good enough" matrix. When CADO-NFS says, it is OK, I'll actually be trying to shift to msieve LA, which will free up the CADO-NFS "farm" for the next run.

All that said, if you want any of the smaller ones that are there or show up, go ahead and grab them. I'll see what's available at the time I'm ready to get something and reserve it then.

2020-03-26, 20:21   #1778
jyb

Aug 2005
Seattle, WA

25·72 Posts

Quote:
 Originally Posted by EdH I did a couple quartic snfs jobs as gnfs and didn't have too much issue. I'm now running 6+5,370 snfs with a quartic to see how it turns out. 8+3,320 would be on my list, if 6+5,370 works OK, but I don't know how soon that might be. After that, depending on how long it takes and whether something smaller turns up, I would look at 9-7,269. But all this might be a while and it's dependent on how 6+5,370 finishes. I kind of expect it to move to LA tomorrow, even though CADO-NFS will be checking later today for a "good enough" matrix. When CADO-NFS says, it is OK, I'll actually be trying to shift to msieve LA, which will free up the CADO-NFS "farm" for the next run. All that said, if you want any of the smaller ones that are there or show up, go ahead and grab them. I'll see what's available at the time I'm ready to get something and reserve it then.
I think you'll find that a GNFS-168 is far easier than an SNFS-230 quartic. If you really finish the sieving for 6+5,370 by tomorrow, then I'll assume you have access to an awful lot of computing power.

I suspect 8+3,320 would also be substantially faster by GNFS.

2020-03-26, 20:34   #1779
EdH

"Ed Hall"
Dec 2009
Adirondack Mtns

23×421 Posts

Quote:
 Originally Posted by jyb I think you'll find that a GNFS-168 is far easier than an SNFS-230 quartic. If you really finish the sieving for 6+5,370 by tomorrow, then I'll assume you have access to an awful lot of computing power. I suspect 8+3,320 would also be substantially faster by GNFS.
You are probably quite right about it being longer, which is why I'm testing it. At just over two days into sieving, I have just passed 100M relations. But I don't know how close I am to a workable matrix, or how much the relations found will taper off. My computing power is antique - several i7's and i5's.

2020-03-26, 22:17   #1780
swellman

Jun 2012

B3616 Posts

Quote:
 Originally Posted by swellman I presume 8+3_320 (C175) is best factored with GNFS, correct? The quartic SNFS is difficulty 231 which will be slow to sieve I think. Anybody want 9-7_269 (GNFS 167) or should I grab it for NFS@Home?
Robert Balfour just reserved 9-7_269.

I can start poly searching 8+3_320 later tonight unless Ed wants it.

2020-03-26, 23:26   #1781
jyb

Aug 2005
Seattle, WA

25·72 Posts

Quote:
 Originally Posted by EdH You are probably quite right about it being longer, which is why I'm testing it. At just over two days into sieving, I have just passed 100M relations. But I don't know how close I am to a workable matrix, or how much the relations found will taper off. My computing power is antique - several i7's and i5's.
Can you tell me what parameters you're using for the sieving? Does CADO-NFS have settings that map reasonably clearly to the ones in ggnfs? I'm currently sieving for 5+3,1185L, which only has an SFNS difficulty of 222 (though it's a quartic, of course), and as expected, it's a real slog. I've been at it for about 24 hours and have only accumulated about 22M relations. Either your parameters are way better than mine, or you have a lot more hardware to throw at it than I do.

2020-03-26, 23:43   #1782
R.D. Silverman

Nov 2003

26·113 Posts

Quote:
 Originally Posted by jyb Can you tell me what parameters you're using for the sieving? Does CADO-NFS have settings that map reasonably clearly to the ones in ggnfs? I'm currently sieving for 5+3,1185L, which only has an SFNS difficulty of 222 (though it's a quartic, of course), and as expected, it's a real slog. I've been at it for about 24 hours and have only accumulated about 22M relations. Either your parameters are way better than mine, or you have a lot more hardware to throw at it than I do.
Query: How much are you skewing the (size of) the factor bases? The rational side
should have a much bigger base and LP bound. [for quartics].

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