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R.D. Silverman 2007-09-17 12:14

Status
 
What's the status of 5,317-, 6,283-, 5,323- etc? I understand that
they finished sieving some time ago.

Wacky 2007-09-17 15:26

Paul has been processing 6,283-.
On Sept 5, he reported that he had produced a 4.75M matrix and that it would require about 12 more days to run the Block Lanzcos phase on his machine. So I expect to hear something from him soon.

Subsequently, I began processing 5,317-. I managed to produce a 4.38M matrix but my 32 bit processing is much slower than Paul's 64 bit implementation. I'd done about 20%, but do not expect to finish before late October.

5,323- is our current sieving. We have done about 40% and should complete that sieving mid-October if we are able to continue at the current rate.

xilman 2007-09-18 01:39

[QUOTE=Wacky;114470]Paul has been processing 6,283-.
On Sept 5, he reported that he had produced a 4.75M matrix and that it would require about 12 more days to run the Block Lanzcos phase on his machine. So I expect to hear something from him soon.[/QUOTE]I'm typing on a laptop in a hotel room just off Harvard Square right now and accessing my home systems is possible but not entirely simple. When I last checked, some hours ago, the matrix still had a few hours to run. Therefore, it should be close to finished now.

If I can complete the factorization from here I will. Otherwise, it will have to wait until I return home (doubtless jetlagged) on Thursday.


Paul

P.S. Actually, it is impossible right now. It appears that my home ADSL link is down.

xilman 2007-09-18 22:37

[QUOTE=xilman;114517]I'm typing on a laptop in a hotel room just off Harvard Square right now and accessing my home systems is possible but not entirely simple. When I last checked, some hours ago, the matrix still had a few hours to run. Therefore, it should be close to finished now.

If I can complete the factorization from here I will. Otherwise, it will have to wait until I return home (doubtless jetlagged) on Thursday.


Paul

P.S. Actually, it is impossible right now. It appears that my home ADSL link is down.[/QUOTE]The linear algebra had finished by this morning (Boston time) and so I kicked off the square root stage. The latter is expected to take an hour or more so I left it running. After the day's business here I tried to pick up the factors but the ADSL was down again.

With a bit of luck I may be able to get the factors tomorrow.


Paul

Wacky 2007-09-21 17:19

Last night, Paul reported to me that he had returned to England and retrieved the following information before going to bed after an exhausting trip.

[QUOTE]6,283-

Probable prime factor 1 has 99 digits:
447124831877025366689793129436873423163216894462385022533572097231958503707190221729170132612703957
Probable prime factor 2 has 75 digits:
138457361320915478919381975760508114488979126852819238404548238145324558533

so not an ECM miss, even by Bruce's standards.
[/QUOTE]

I'm sure that it is likely that he will add some more details after he recovers.


On 5,317-, I have completed 30% of the Block Lanczos iterations.

And we have completed approximately 50% of the sieving for 5,323-.

Jwb52z 2007-09-22 15:26

Is the actual NFSNet project website going to be updated soon with all this new information about what has been completed since April? That was the date of the last bit of news on the website. I understand if the person who does that needs to recover from his travelling, but as I help keep one of the biggest DC project websites updated, it would be nice to make some official news about it from the website, no hurry though.

bdodson 2007-09-22 16:26

[QUOTE=Jwb52z;114870]Is the actual NFSNet project website going to be updated soon ... I understand if the person who does that needs to recover from his travelling, ...[/QUOTE]

Xilman does post-processing after sieving, and sets sieving regions
for the new numbers; not web page maintenance. The person that
used to do the web page and stats retired from NFSNET, and hasn't
been replaced. Fivemack/Tom did some interim updates, perhaps he
could do another round? -bdodson

Jwb52z 2007-09-24 21:54

Thank you so much for the quick answer to my question. There are a great many people who visit the DC site I help with and I'm sure they are interested in what's going on with things. :)

Wacky 2007-09-28 22:01

5,317- Factored
 
I am pleased to report that, with the assistance of "frmky" Greg Childers (CalState-Fullerton) and utilizing code from msieve ("jasonp" Jason Papadopoulos), NFSNet has completed the factorization of 5,317-.

Greg reported [QUOTE]Fri Sep 28 12:06:02 2007 prp85 factor: 1173266048118996938584719882501239841331337879112270918586790280760729499132694039331
Fri Sep 28 12:06:02 2007 prp110 factor: 78784317656768133239109671345422644991678073397834197717116145126532590520938482143011654153492533979880370291

Greg[/QUOTE]

Thanks to all who helped in this effort. I'm sure that Greg will have something to add about his part of the effort.

In the meantime, we continue to sieve for 5,323-, having reached about 2/3 of the estimated interval. With both Paul and Greg capable of doing the post processing in a reasonable timeframe, we can use some additional help in the sieving.

Please join us.

On the behalf of the entire NFSNet Factoring Group,
Richard "Wacky" Wackerbarth

frmky 2007-09-28 22:38

Just a few details... As far as I am aware, this the largest SNFS factorization to date completed with Jason's msieve. Approximately 52 million relations were converted from CWI to GGNFS format, then fed to msieve running on a 1.8 GHz single-core Opteron 144 system with 3 GB of memory in 64-bit Linux.

The filtering took about 4 hours to complete, and used 2.6 GB of memory. It produced a final 4945096 x 4945296 matrix with weight 430746398. After setting aside the dense rows due to the quadratic characters and small primes, Block Lanczos was started on a 4945048 x 4945296 matrix with weight 325847903 (a bit less than 66 nonzero entries per column). Although the calendar time was a bit longer due to concurrently running processes, the runtime was just over 6 days, and used 1.4 GB of memory. Each square root run took about 2 1/4 hours and used about 1 GB of memory. The factors were found on the 5th dependency.

Greg

jasonp 2007-09-29 02:55

[QUOTE=frmky;115323]Just a few details... As far as I am aware, this the largest SNFS factorization to date completed with Jason's msieve. [/QUOTE]
I must say, this announcement has just made my evening. Richard, is there any information about the matrix generated by the CWI suite, and how long the linear algebra would have taken?

frmky 2007-09-29 05:02

The CWI suite produced a slightly smaller but denser matrix:

[QUOTE]Matrix has 4368656 rows and 4386633 columns.
Remaining matrix weight is 326654668, density 0.0017%.
Average prime weight 74.77, average relation-set weight 74.47.
[/QUOTE]

The BL was in progress, but I believe was expected to take about 6 weeks on Richard's 32-bit machine.

Greg

bdodson 2007-09-29 13:45

[QUOTE=jasonp;115339]I must say, this announcement has just made my evening. ...[/QUOTE]

Mine too! Even with the benefit of a heads-up from Richard; a
real solid improvement in the matrix step (and filtering, even).
Congratulations Greg and Jason.

With the backlog cleared, we ought to be able to go on to finish
the last of Bob's 768-bit list. Although, if I read the replies to
King's poll correctly, Bob himself was voting in favor of harder
Most Wanted base-2's. I gather that there was an intended
follow-up poll; and append the candidates below. I'd like to
see them all done; any order is good. More sieving contributors
for NFSNET would move things along more quickly.

Of course (as Greg has pointed out), someone to fill the missing
Stat's position would also help. For that matter, no reason for
NFSNET to monopolize these candidates, if someone else is
interested in steping up ...

-Bruce

[QUOTE] You could start a new ballot ... Keep the options as
7,263-
6,284+
2,787-
2,776+
7,268+ [/QUOTE]

Rest of the 768-bit list is 6,292+ 7,269- and 7,271-
presumably for after the above ones from bases 6 and 7.
The other Most wanted base-2's seem to be 2,779+
and 2,787+ with 2,776+ (above) More wanted.

bdodson 2007-09-30 01:43

We have a winner!
 
[QUOTE=bdodson;115356] ...I gather that there was an intended
follow-up poll; and append the candidates [above]
...
Rest of the 768-bit list is 6,292+ 7,269- and 7,271-
presumably for after the above ones from bases 6 and 7.
The other Most wanted base-2's seem to be 2,779+
and 2,787+ with 2,776+ (above) More wanted.[/QUOTE]

That was quick; 6, 284+ wins. (Unless ECMNET gets
a factor within the week.) Suppose 6,292+ would serve
as a replacement for a poll. If that one wins next, the
768-bit list would be down to four last base-7's. -bd

R.D. Silverman 2007-10-01 12:33

[QUOTE=bdodson;115356]Mine too! Even with the benefit of a heads-up from Richard; a
real solid improvement in the matrix step (and filtering, even).
Congratulations Greg and Jason.

With the backlog cleared, we ought to be able to go on to finish
the last of Bob's 768-bit list. Although, if I read the replies to
King's poll correctly, Bob himself was voting in favor of harder
Most Wanted base-2's. [/QUOTE]

The only reason for my preference was that I had promised Dick Lehmer that
I would push to finish the base 2 tables that were incomplete from the
1st edition of the book. They have been around for a long time; the
others are relative newcomers. Some time ago, NFSNET had asked for
suggestions for some "easier" numbers. I had suggested the 768-bit list as
an alternative to the harder base 2 numbers.

In fact, if NFSNET wants to make a effort to finish the base 2 tables
through 800 bits, I will put aside my work and help with the sieving.
My siever is a good deal faster than the one used by NFSNET.

There are two numbers left from 2- (one is supposedly "in progress", but
I won't hold my breath), Three from the 2+, two from the 2,4K+ and
6 from the 2LM table (one of which will finish in about 2.5 days).

bdodson 2007-10-01 17:38

[QUOTE=R.D. Silverman;115437]
There are two numbers left from 2- (one is supposedly "in progress", but
I won't hold my breath), Three from the 2+, two from the 2,4K+ and
6 from the 2LM table (one of which will finish in about 2.5 days).[/QUOTE]

Substantial progress since the last time we looked; finishing 2,1582L c162
will move 2,1598M C160 up into a fifth hole; with the 12 remaining all readily
visible on Sam's page. Base-2's are fine with me; the only concern
being that if there aren't enough sievers we'd drift up towards six months
of sieving, which is a long time to wait for someone just considering
joining. -bd

R.D. Silverman 2007-10-05 12:39

[QUOTE=bdodson;115457]Substantial progress since the last time we looked; finishing 2,1582L c162
will move 2,1598M C160 up into a fifth hole; with the 12 remaining all readily
visible on Sam's page. Base-2's are fine with me; the only concern
being that if there aren't enough sievers we'd drift up towards six months
of sieving, which is a long time to wait for someone just considering
joining. -bd[/QUOTE]

Here is 2,1582L. 2,1962M is filtering. 2,1630M is sieving.
2,1630M requires a quartic. It will be quite slow.

2,1582L c162 = p70.p92

p70 = 4785290367491952770979444950472742768748481440405231269246278905154317
p92 = 94732691570793956856759198414911779734119524415635396799864941098330965560269355785101434237

fivemack 2007-10-05 15:19

How do you use the additional factor p of an Aurifeuillian factor?

Taking out a factor p from x^p+1 involves the factorisation x^p+1 = (x+1)(x^{p-1}-x^{p+2}...\pm 1); the Aurifeuillian factors are from 4x^4+1=(2x^2+1)^2-(2x)^2 = (2x^2-2x+1) (2x^2+2x+1); but I don't see how those forms fit together so you can do both.

What was the polynomial for 2,1582L or 2,1962M?

fivemack 2007-10-05 15:44

Ah, I've figured this out.

Say x=28M+14.

factor(2^14*x^28+1) is
[code]
[2*x^2 - 2*x + 1 1]
[2*x^2 + 2*x + 1 1]
[64*x^12 - 64*x^11 + 32*x^10 - 16*x^8 + 16*x^7 - 8*x^6 + 8*x^5 - 4*x^4 + 2*x^2 - 2*x + 1 1]
[64*x^12 + 64*x^11 + 32*x^10 - 16*x^8 - 16*x^7 - 8*x^6 - 8*x^5 - 4*x^4 + 2*x^2 + 2*x + 1 1]
[/code]

now put u=2x+1/x; x^6*(u^6+2*u^5-10*u^4-20*u^3+16*u^2+32*u+8) is one factor and
x^6*(u^6-2*u^5-10*u^4+20*u^3+16*u^2-32*u+8) the other.

So it was just a matter of picking the right substitution, as I suppose SNFS polynomial generation always is.

12k+6 gives you a quartic [4 -4 2 -2 1] natively, or you can do the substitution to turn it into a quadratic and then change X and scale to get a sextic (which must be better than a quartic at >180 digits); 20k+10 gives you an octic which turns into a quartic and is annoying at >180 digits.

Have I missed anything out?

R.D. Silverman 2007-10-05 17:42

[QUOTE=fivemack;115756]How do you use the additional factor p of an Aurifeuillian factor?

Taking out a factor p from x^p+1 involves the factorisation x^p+1 = (x+1)(x^{p-1}-x^{p+2}...\pm 1); the Aurifeuillian factors are from 4x^4+1=(2x^2+1)^2-(2x)^2 = (2x^2-2x+1) (2x^2+2x+1); but I don't see how those forms fit together so you can do both.

What was the polynomial for 2,1582L or 2,1962M?[/QUOTE]

For 1582L: x^6 + 2x^5 - 10x^4 - 20x^3 + 16x^2 + 32x + 8

For 1962M: x^6 - 12x^4 + 4x^3 + 36x^2 - 24x - 8

R.D. Silverman 2007-10-05 17:46

[QUOTE=fivemack;115758]Ah, I've figured this out.

Say x=28M+14.

factor(2^14*x^28+1) is
[code]
[2*x^2 - 2*x + 1 1]
[2*x^2 + 2*x + 1 1]
[64*x^12 - 64*x^11 + 32*x^10 - 16*x^8 + 16*x^7 - 8*x^6 + 8*x^5 - 4*x^4 + 2*x^2 - 2*x + 1 1]
[64*x^12 + 64*x^11 + 32*x^10 - 16*x^8 - 16*x^7 - 8*x^6 - 8*x^5 - 4*x^4 + 2*x^2 + 2*x + 1 1]
[/code]

now put u=2x+1/x; x^6*(u^6+2*u^5-10*u^4-20*u^3+16*u^2+32*u+8) is one factor and
x^6*(u^6-2*u^5-10*u^4+20*u^3+16*u^2-32*u+8) the other.

So it was just a matter of picking the right substitution, as I suppose SNFS polynomial generation always is.

12k+6 gives you a quartic [4 -4 2 -2 1] natively, or you can do the substitution to turn it into a quadratic and then change X and scale to get a sextic (which must be better than a quartic at >180 digits); 20k+10 gives you an octic which turns into a quartic and is annoying at >180 digits.

Have I missed anything out?[/QUOTE]



You got it.

R.D. Silverman 2007-10-05 18:15

[QUOTE=fivemack;115758]Ah, I've figured this out.

Say x=28M+14.

factor(2^14*x^28+1) is
[code]
[2*x^2 - 2*x + 1 1]
[2*x^2 + 2*x + 1 1]
[64*x^12 - 64*x^11 + 32*x^10 - 16*x^8 + 16*x^7 - 8*x^6 + 8*x^5 - 4*x^4 + 2*x^2 - 2*x + 1 1]
[64*x^12 + 64*x^11 + 32*x^10 - 16*x^8 - 16*x^7 - 8*x^6 - 8*x^5 - 4*x^4 + 2*x^2 + 2*x + 1 1]
[/code]

now put u=2x+1/x; x^6*(u^6+2*u^5-10*u^4-20*u^3+16*u^2+32*u+8) is one factor and
x^6*(u^6-2*u^5-10*u^4+20*u^3+16*u^2-32*u+8) the other.

So it was just a matter of picking the right substitution, as I suppose SNFS polynomial generation always is.

12k+6 gives you a quartic [4 -4 2 -2 1] natively, or you can do the substitution to turn it into a quadratic and then change X and scale to get a sextic (which must be better than a quartic at >180 digits); 20k+10 gives you an octic which turns into a quartic and is annoying at >180 digits.

Have I missed anything out?[/QUOTE]

I may have missed something. For example, for 2,1914M we get a
quartic: [4,4,2,2,1] with root 2^159 . This becomes a quadratic
x^2 + 2x - 2 with root 2^160 + 2^-159. To turn this into a sextic
we make the substitution z^6 = x^2 giving z^6 + 2z^3 - 2, but
the root is now z=(2^160 + 2^-159)^1/3. Computing a cube root
mod N is as hard as factoring N itself. How do you suggest computing this
cube root?

fivemack 2007-10-05 19:42

Good point about the cube root; I hadn't thought what was happening on the linear side, and just remembered that the quadratic for x^3-1 can be turned trivially into a sextic. Sorry to have raised your hopes about 2,1914M.

Going through, 2,1962M is actually managing to use the factor nine by working with the factorisation of 2^18*x^36+1 ... I didn't expect that to be possible. Cool.

[in the past you've occasionally posted things here suggesting that you don't have access to computational algebra; I'm doing all of this with pari/gp, which is conveniently free software, though I'm sure you've got hold of that yourself]

bdodson 2007-10-08 09:12

[QUOTE=bdodson;115372]That was quick; 6, 284+ wins. (Unless ECMNET gets
a factor within the week.) Suppose 6,292+ would serve
as a replacement for a poll. If that one wins next, the
768-bit list would be down to four last base-7's. -bd[/QUOTE]

No; no factor in my 3rd & last t50 on 6,284+. But 6,292+ isn't
going to do as a replacement:

p60 = 151634244917416206035101114864937647283016448179107389644473

with prime cofactor. One more number to go to finish the 3rd
t50 on the last of the c190-c233's in difficulty 220-229. This one
was More wanted, 6th on the top10. -Bruce

R.D. Silverman 2007-10-09 21:44

2,1962M
 
Here is 2,1962M C173 = p54.p119

p54 = 561070572288256277136602810062157316007570131157641589
p119 = 52548716528304902570734222019216090488579184876231505008640646786326028262229620519239651894875787945135414973991400093

2,1630M is in progress. It will take a while since a quartic is sub-optimal.

R.D. Silverman 2007-10-11 11:52

[QUOTE=bdodson;115457]Substantial progress since the last time we looked; finishing 2,1582L c162
will move 2,1598M C160 up into a fifth hole; with the 12 remaining all readily
visible on Sam's page. Base-2's are fine with me; the only concern
being that if there aren't enough sievers we'd drift up towards six months
of sieving, which is a long time to wait for someone just considering
joining. -bd[/QUOTE]


Kleinjung finished 2,799- C188 = p56.p133

fivemack 2007-10-11 23:50

This may be an unnecessarily contentious post, but do you consider Kleinjung's result an ECM miss? I think it's marginal; a curve at the 55-digit level takes about 30 minutes on hardware on which I'd expect 240-digit SNFS to take around 20,000 hours, and 40,000 curves would probably have picked up a p56, but I'm not sure that ECM on that number is the first use to which I'd have put 20,000 CPU-hours.

bdodson 2007-10-12 02:23

[QUOTE=fivemack;116163]This may be an unnecessarily contentious post, but do you consider Kleinjung's result an ECM miss? I think it's marginal; a curve at the 55-digit level takes about 30 minutes on hardware on which I'd expect 240-digit SNFS to take around 20,000 hours, and 40,000 curves would probably have picked up a p56, but I'm not sure that ECM on that number is the first use to which I'd have put 20,000 CPU-hours.[/QUOTE]

It seems to me that, by what I understand as the conventional use,
what you're discussing here is a hypothetical. To be an ecm miss, where
ecm didn't do what we expected, you'd have had to actually run the
20,000 cpu hours. Optimal use of computing resources for ecm also
has a built-in failure rate. If 40,000 curves with B1=110M is an optimal
test for a known p55, we're supposed to stop at probabilty 1-1/e of
finding the factor, allowing 1/e (a bit over 30%) of a chance of not
getting that specific p55; re-estimating the next most likely factor size,
presumably p60, and switch B1 to look for p60's. So if there were 10
sieving candidates with a p55, we're supposed to find 7 of them, and leave
the other 3. So at/near the bleeding edge of performance ecm, no
single prime factor found by sieving instead of ecm is ecm's fault. So
as I understand the issue, the curves have to have actually be run,
and for a single instance to qualify as an ecm miss, the factor should
be notably below the level to which ecm was run.

In this case, Kleinjung's reservation was way back in late June (it's
on the July 1 "who's doing what"), so there were only 2*t50 bdodson
curves run; perhaps a somewhat larger (2+epsilon)*t50 since this
was a base-2 number. For me to say that ecm (rather than it's
operators, deciding what numbers to feed into ecm) had missed a
specific factor of a number run to 2*t50, I'd be thinking something
like p47-p48. Peter has a term of "removing" an ecm factor size, rather
than "finding", for which one runs twice the number of curves "expected";
lowering the probablilty of leaving a factor of that size to 1/(e^2). So if
you were having hesitations about the 20,000 cpuhours, I'm expecting
that if it were a question of 40,000 that you'd much rather have spent
the time sieving, for which we'd be making certain progress towards
the factorization.

Taking the two recent small factors together, Bob's p54 and Thorsten's
p56, they seem entirely consistent with the Silverman-Wagstaff analysis --
if an ecm t50 has failed to find a factor, the next most likely factor size
to look for is p55. And we're still a long way from being willing to run t55's
on numbers of small snfs difficulty. Actually, I find these factor sizes
somewhat encouraging: if/when almost all of the gnfs/snfs smallest factor
sizes are above p80, ecm will no longer be an attractive method.
-Bruce

PS - In the pdf JasonP points to on the kilobit snfs, the authors are
grumbling that if they'd known that there was a p80 they might have
run some more ecm. Sounds like we're within a generation or two of
the first p80 referred to as an ecm miss! (That's cpu/memory generations;
sooner than one might expect.)

R.D. Silverman 2007-10-12 15:13

[QUOTE=bdodson;116170]

<snip>

And we're still a long way from being willing to run t55's
on numbers of small snfs difficulty. Actually, I find these factor sizes
somewhat encouraging: if/when almost all of the gnfs/snfs smallest factor
sizes are above p80, ecm will no longer be an attractive method.
[/QUOTE]

I would not call M799 "small snfs difficulty". Otherwise, we are in total
agreement.

BTW, I don't think the p56 is even close to being an ECM miss.

The p51 from 11,251+ might be.

bdodson 2007-10-13 14:15

[QUOTE=R.D. Silverman;116197]I would not call M799 "small snfs difficulty". Otherwise, we are in total agreement.
...
The p51 from 11,251+ might be.[/QUOTE]

Thanks for the wake-up call! On M799, difficulty 240.52, I have
these in difficulty 230-249. Most of the grid cpu's are in 250-361
both the larger memory P4s (B1=110M) and the core2s (B1=260M),
split c211-c233 and c190-c210. The Opterons just finished a 3rd
t50 on c190-c233 with difficulty 220-229.99; and are starting in
on 230-239.99. The new dual xeon quads are warming up on
240-249.99, also c190-c233. So far and away, most of my curves
are going on numbers with difficulty above 241!

I've been referring to c147-c154's as "soon to be smaller-but-needed"
for a year-or-so already; but those are shrinking steadily, leaving
c155-c169, and even c170-c189 as "smaller". After effects, perhaps,
of my extended run in c251-c365. If we finish the ones with (snfs)
difficulty below 220 for which there's a quintic or sextic, these
new-smaller c155-c179's will shrink towards degree 4's and/or gnfs's.
-Bruce :rolleyes:

bdodson 2007-10-18 15:55

Smokin' !!
 
[QUOTE=R.D. Silverman;115437]... I had promised Dick Lehmer that I would push to finish the base 2 tables ...
Some time ago, NFSNET had asked for suggestions for some "easier"
numbers. I had suggested the 768-bit list as an alternative to the
harder base 2 numbers.

In fact, if NFSNET wants to make a effort to finish the base 2 tables
through 800 bits, ...[/QUOTE]

Looks like you're getting your wish, nfsnet seems to have completed
their run on the 768-bit list with 6,284+. Perhaps someone else will
pick up the remaining ones (the last one has finished 3*t50).

As I recall the NFSNET charter, the objective isn't so much cleaning
up the numbers within a comfortable range, but to push on to larger
benchmarks. So as Xilman observes, 2,779+.C212 is difficulty 235,
the largest we've done in a while (Lehigh seems to have been the
last to switch); and the winner of the next number "vote" was
10,239-.C228, difficulty 239. Looks like Thorsten was headed in the
right direction, with difficulties in the 240's. -Bruce

Wacky 2007-10-31 02:02

This evening, Greg reported to me:
[QUOTE]
5,323- finished successfully. The factors are
prp54 factor: 824025642333621472612253607491152025643258690550015151
prp61 factor: 4520075300365525822415973296109200878340148487916084028121991
prp72 factor: 132981150324062454692451481044833258173562011479994362058454095433879531
[/QUOTE]

This factoring utilized a combination of the CWI suite and post processing from msieve.

87.9M unique relations were collected by line sieving.

I then processed the data removing the singletons and cliques to the point that there were 3.4M excess for ideals > 10M.
Those remaining 26M relations were sent to California where Greg used msieve to further reduce the data to a 6.4M matrix.
The Block Lanczos phase ran from Thu Oct 25 14:33:54 2007 to Tue Oct 30 03:36:20 2007.
We would like to thank Greg's colleague who gave up his machine not only for the weekend, but also all day Friday and Monday to run the matrix solution.

We continue sieving for 2,779+.C212 and should switch to 10,239-.C228 early next month.

bdodson 2007-11-01 21:03

[QUOTE=Wacky;117421]We continue sieving for 2,779+.C212 and should switch to 10,239-.C228 early next month.[/QUOTE]

5,323- was selected at the last moment; in fact, the project file
is in the same email as confirmation of the selection. So no extra ecm.
I see a report of 2*t50, and the selection was before Bob's "(near) miss"
of a p53, which was when I started que-ing 3rd t50's. I did a bit
better with 6, 284+ with a last minute 3rd t50 (thanks to an early
"whos doing what?" from Sam, which had the nfsnet reservation). But
5,323- was earlier, and a 2*t50 effort is less than half of what's
needed for the p54; ecm didn't get a fair shot.

The current 779+ did get a 3rd t50; and the base-10 next number
got 4*t50. With current resources we wouldn't drop back to difficulty
below 230. Seems like M787 would be about the best we could do
in the mid-230 range, at the top of the most wanted list. We could
apply the same parameters to pick up 2,787+ at the same difficulty.
Or is there something in difficulty 240-249.99 that would be a better,
more difficult challenge? Setting the number early would give me a
better chance to make sure that the 3rd t50's been done, and get a
better chance at any p54-p69's by continuing on toward t55. I can
try guessing a likely range or ranges, but a definite early selection
would be best. -Bruce

Wacky 2007-11-22 20:44

This morning, Greg reported:

2,779+ is done just in time for Thanksgiving. The factors are

prp86 factor: 17315878129048863927974905480696448369723747093035498799994851681384411684778961025249
prp127 factor: 1241587275642193613677401209382009830084399769371108904801198294935706207364264832500354031378698910359793960404372927442514937



Here are some of the interesting lines from the log

Wed Nov 7 21:05:35 2007 Msieve v. 1.29

Wed Nov 7 21:05:35 2007 factoring 21499173951598023655871526129741238864252274176505248438905816972331478841874026717266127459812853910615830233333737201439633130982196868280103768992238493630431515155684471825756247809234523310884830836516644313 (212 digits)
Wed Nov 7 21:05:35 2007 commencing number field sieve (212-digit input)

Wed Nov 7 21:31:59 2007 found 90496938 unique relations

Thu Nov 8 01:06:57 2007 matrix is 7490253 x 7490451 with weight 666958089 (avg 89.04/col)

Thu Nov 8 01:07:48 2007 commencing Lanczos iteration
Wed Nov 21 12:03:07 2007 lanczos halted after 118456 iterations (dim = 7490189)

Wed Nov 21 20:06:52 2007 reading relations for dependency 4

Wed Nov 21 22:47:26 2007 prp86 factor: 17315878129048863927974905480696448369723747093035498799994851681384411684778961025249
Wed Nov 21 22:47:26 2007 prp127 factor: 1241587275642193613677401209382009830084399769371108904801198294935706207364264832500354031378698910359793960404372927442514937
Wed Nov 21 22:47:27 2007 elapsed time 337:41:52

wreck 2007-11-26 00:30

SubmitResults() failed
 
These several days I often get "failed" messages, some times it is "RequestAssignment() failed", some times "Received assignment ( IDLE 0-0)".This maybe because there is no task temporarily.But why there are so many "SubmitResults() failed" messages.I'm really sick about it.

[code]
23:33:59 NFSNET Client - $Revision: 1.17 $
23:33:59 Initializing...
23:33:59 Initialized.
23:33:59 Requesting assignment...
23:34:01 Received assignment ( REDIRECT 0-0)...
23:34:03 Requesting assignment...
23:34:26 Received assignment ( REDIRECT 0-0)...
23:34:36 Requesting assignment...
23:34:40 Received assignment (Bristol 10_239M_1 10521035-10521291)...
23:34:40 Getting project details...
23:34:46 Building .polys file...
23:34:46 Building .in file...
23:34:46 Updating project .in file with assigned range...
23:34:46 Launching rootfinder...
# Find roots of polynomials for Number Field Sieve
# Intel x86 (Windows) V 1.0 RC1
# Department of Mathematics, Oregon State University
# Corvallis, OR 97331-4605 USA
# and
# Centrum voor Wiskunde en Informatica
# Kruislaan 413
# 1098 SJ Amsterdam
# The Netherlands
# Running on XHX034 at Mon Nov 26 07:34:46 2007
Polynomials read from projects\10_239M_1\polys.txt.
# n = 16238581280990058326129559737298355994869848494632165854073565620201800350
58451047371340703573622691199920338919238967077426600651484835722446569697612562
08962241824944638737217461295395400432531624931235045560966776497496089919
# root = 10000000000000000000000000000000000000000
# npoly = 2
# Polynomial 1:
# X - 10000000000000000000000000000000000000000
# Polynomial 2:
# X^6 - 10
# Maximal fbbound = 30000000
Roots will be written to projects\10_239M_1\factor_base.txt, in ASCII format.
ln_abquot = -0.300, sum_logs_squared = 3973.514
ln_abquot = 0.000, sum_logs_squared = 3933.7122
ln_abquot = 0.300, sum_logs_squared = 3896.4756
ln_abquot = 0.600, sum_logs_squared = 3902.7517
ln_abquot = 0.120, sum_logs_squared = 3917.6835
ln_abquot = 0.390, sum_logs_squared = 3891.7477
ln_abquot = 0.453, sum_logs_squared = 3892.5022
ln_abquot = 0.363, sum_logs_squared = 3892.465
ln_abquot = 0.409, sum_logs_squared = 3891.6287
ln_abquot = 0.422, sum_logs_squared = 3891.7283
ln_abquot = 0.403, sum_logs_squared = 3891.6317
ln_abquot = 0.413, sum_logs_squared = 3891.6431
ln_abquot = 0.407, sum_logs_squared = 3891.6267
ln_abquot = 0.406, sum_logs_squared = 3891.6268
ln_abquot = 0.408, sum_logs_squared = 3891.6271
ln_abquot = 0.407, sum_logs_squared = 3891.6266
ln_abquot = 0.407, sum_logs_squared = 3891.6266
ln_abquot = 0.406, sum_logs_squared = 3891.6266
ln_abquot = 0.407, sum_logs_squared = 3891.6266
ln_abquot = 0.407, sum_logs_squared = 3891.6266
ln_abquot = 0.407, sum_logs_squared = 3891.6266
ln_abquot = 0.407, sum_logs_squared = 3891.6266
ln_abquot = 0.407, sum_logs_squared = 3891.6266
ln_abquot = 0.407, sum_logs_squared = 3891.6266
ln_abquot = 0.407, sum_logs_squared = 3891.6266
ln_abquot = 0.407, sum_logs_squared = 3891.6266
ln_abquot = 0.407, sum_logs_squared = 3891.6266
ln_abquot = 0.407, sum_logs_squared = 3891.6266
ln_abquot = 0.407, sum_logs_squared = 3891.6266
Suggested ratio for (max a)/(max b) = 1.502
Caution -- siever input uses (width a) = 2*(max a) and range for b.
This is because a can be negative but b must be positive.

p = 632881, trials = 8
p = 764689, trials = 8
p = 1007557, trials = 8
p = 1655569, trials = 8
p = 1962997, trials = 8
p = 4173241, trials = 8
p = 5010013, trials = 8
p = 5206321, trials = 8
p = 5619517, trials = 8
p = 6345307, trials = 8
p = 9149053, trials = 8
p = 11089963, trials = 8
p = 12543997, trials = 8
p = 13478917, trials = 8
p = 14795839, trials = 8
p = 16161253, trials = 8
p = 18022801, trials = 8
p = 19295677, trials = 8
p = 19320877, trials = 8
p = 19897333, trials = 8
p = 20637997, trials = 8
p = 22674013, trials = 8
p = 22684369, trials = 8
p = 23675173, trials = 8
p = 25244437, trials = 8
p = 26606557, trials = 8
p = 27651787, trials = 8
p = 28090507, trials = 8
p = 28113037, trials = 8
p = 28274443, trials = 8
At 1800001-st prime: 29005549
Polynomial 1 has 1857859 roots for 1857859 primes
0 factors: 0 primes ( 0.00%)
1 factors: 1857859 primes (100.00%)

Polynomial 2 has 1857154 roots for 1857859 primes
0 factors: 1238603 primes ( 66.67%)
1 factors: 2 primes ( 0.00%)
2 factors: 464593 primes ( 25.01%)
3 factors: 0 primes ( 0.00%)
4 factors: 0 primes ( 0.00%)
5 factors: 0 primes ( 0.00%)
6 factors: 154661 primes ( 8.32%)



Statistics for sieving over projective space:

Polynomial Expected log10 of contribution Variance
1 7.08 27.62
2 6.52 26.72
(random) 7.08 27.45


Statistics for sieving over a line:

Polynomial Expected log10 of contribution Variance
1 7.33 27.79
2 6.79 26.82
(random) 7.33 27.53
23:36:09 Rootfinder is finished...
23:36:09 Launching siever...
00:07:53 Siever finished...
00:07:53 Submitting results...
0
00:08:14 SubmitResults() failed, sleeping for 10 seconds.
Last message was:
00:12:28 SubmitResults() failed, sleeping for 20 seconds.
Last message was:
00:15:58 SubmitResults() failed, sleeping for 40 seconds.
Last message was:
0
00:17:00 SubmitResults() failed, sleeping for 80 seconds.
Last message was:
00:22:24 SubmitResults() failed, sleeping for 160 seconds.
Last message was:
00:29:08 SubmitResults() failed, sleeping for 320 seconds.
Last message was:[/code]

Wacky 2007-11-26 02:01

[QUOTE=wreck;119207]These several days I often get "failed" messages, some times it is "RequestAssignment() failed", some times "Received assignment ( IDLE 0-0)".[/QUOTE]

There are two causes of "IDLE" assignments. Although, except in the past few days when the project manager has been away and allowed the assignment queue to become depleted, it is rare that there is nothing available to be assigned, you can also receive "IDLE" assignments because you are "blacklisted" for failure to properly return results. Given your log excerpts, I think that this is likely to be the cause. As to the cause of the communications problem, I have insufficient information.

I would like to assign you to another server where I can closely monitor the traffic.

I will contact you via e-mail from your registration records.

Richard


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