RSALS (sieving) + Lionel Debroux (filtering) + Jeff Gilchrist (linear algebra + square root), registered as "RSALS Project" on fivemack's server, have factored 8^233-3^233 (GNFS 201.4, SNFS 210.4):

[code]n: 2454428976406129481810213813773243799858629384758806000939798459663844471789608919904344572001218451713996843137802533560056358403084610242473632330109178712589917638474564612013066316381998320236144211
# 8^233-3^233, difficulty: 211.68, skewness: 0.74, alpha: 0.00
skew: 0.740
c5: 9
c0: -2
Y1: -26588814358957503287787
Y0: 1393796574908163946345982392040522594123776
m: 1909564152594990415480745897842303867777969631282134955555218575729166668564694399307563814348772133078381249304738723438235065995887850304634393791198298874896587760716136783062660355130363893400579863
type: snfs
rlim: 23600000
alim: 23600000
lpbr: 29
lpba: 29
mfbr: 58
mfba: 58
rlambda: 2.6
alambda: 2.6[/code]

[code]prp57 factor: 795152984918915359971720068308384714348279613422055858519
prp145 factor: 3086738052874713820874549933717582214781225298045359168326158870732152354004799186001213497885674888645553670120049637265198384203178998961805669[/code]


Sieving of 7^263-4^263 (GNFS 221.8, SNFS 222.3) is in progress.

7,6,235+, SNFS:

[CODE]Tue Jan 26 20:02:28 2010 prp57 factor: 919427716956557427571666967081401676161826048270699146991
Tue Jan 26 20:02:28 2010 prp81 factor: 996791992392025767005699254588398306956488694064047349792696011268885745441871711[/CODE]

Update posted
 

New update has just been posted.


Paul

RSALS (sieving) + Lionel Debroux (filtering + linear algebra + square root), registered as "RSALS Project" on fivemack's server, have factored 7^263-4^263 (GNFS "221.8", SNFS 222.3):

[code]n: 607663665513374212027971560984694467309543593040777118739378042044071194428427531698258155447531450686127654821834979566390398127983994915863194696413959610492502383219742584514221249155619791413729513950916829237182026493
# 7^263-4^263, difficulty: 225.16, skewness: 1.25, alpha: 0.00
# cost: 1.17331e+18, est. time: 558.72 GHz days (not accurate yet!)
skew: 1.251
c5: 16
c0: -49
Y1: -81129638414606681695789005144064
Y0: 616873509628062366290756156815389726793178407
m: 284244003172354212624720071128684708576314479592066753340870113573662821471342671546589925066662323014540013120690347841512482413009016096259242088238405971173011692627625061933443040528717776290882771624512297453295553722
type: snfs
rlim: 39600000
alim: 39600000
lpbr: 30
lpba: 30
mfbr: 60
mfba: 60
rlambda: 2.6
alambda: 2.6[/code]

[code]prp38 factor: 60752941622436266222854676618889763103
prp88 factor: 1001471841636752543886802057724906289674717634401626083435430553435162957708541463194691
prp97 factor: 9987509725178325344485430236095343084327644885285739705763866357927562337177431376753341427135841[/code]

The first factor is a clear ECM miss (I'm surprised it survived long enough in the ECMNet server for NFS to find it !), but we haven't wasted CPU power, as the factorization would have remained easier by SNFS even if that factor had been cut earlier.


You can remove both 8^233-3^233 (post #903 above, three weeks ago) and 7^263-4^263 from fivemack's reservation system.

[QUOTE=debrouxl;205617]
You can remove both 8^233-3^233 (post #903 above, three weeks ago) and 7^263-4^263 from fivemack's reservation system.[/QUOTE]

The reservations are automatically removed when you submit the factors on the reservation page.

[QUOTE=debrouxl;205617]RSALS (sieving) + Lionel Debroux (filtering + linear algebra + square root), registered as "RSALS Project" on fivemack's server, have factored 7^263-4^263 (GNFS "221.8", SNFS 222.3):

[code]n: 607663665513374212027971560984694467309543593040777118739378042044071194428427531698258155447531450686127654821834979566390398127983994915863194696413959610492502383219742584514221249155619791413729513950916829237182026493
# 7^263-4^263, difficulty: 225.16, skewness: 1.25, alpha: 0.00
# cost: 1.17331e+18, est. time: 558.72 GHz days (not accurate yet!)
skew: 1.251
c5: 16
c0: -49
Y1: -81129638414606681695789005144064
Y0: 616873509628062366290756156815389726793178407
m: 284244003172354212624720071128684708576314479592066753340870113573662821471342671546589925066662323014540013120690347841512482413009016096259242088238405971173011692627625061933443040528717776290882771624512297453295553722
type: snfs
rlim: 39600000
alim: 39600000
lpbr: 30
lpba: 30
mfbr: 60
mfba: 60
rlambda: 2.6
alambda: 2.6[/code]

[code]prp38 factor: 60752941622436266222854676618889763103
prp88 factor: 1001471841636752543886802057724906289674717634401626083435430553435162957708541463194691
prp97 factor: 9987509725178325344485430236095343084327644885285739705763866357927562337177431376753341427135841[/code]

The first factor is a clear ECM miss (I'm surprised it survived long enough in the ECMNet server for NFS to find it !), but we haven't wasted CPU power, as the factorization would have remained easier by SNFS even if that factor had been cut earlier.


You can remove both 8^233-3^233 (post #903 above, three weeks ago) and 7^263-4^263 from fivemack's reservation system.[/QUOTE]Thanks. I'll try to get an update to the web pages out today.

Not sure about the ECM miss. It looks very much like one on the face of it but I don't know how long the composite has been reserved. If it was a long time ago, it's quite possible that the ECM effort hadn't reached the p40 level of testing.


Paul

[QUOTE=debrouxl;202937]RSALS (sieving) + Lionel Debroux (filtering) + Jeff Gilchrist (linear algebra + square root), registered as "RSALS Project" on fivemack's server, have factored 8^233-3^233 (GNFS 201.4, SNFS 210.4):

prp57 factor: 795152984918915359971720068308384714348279613422055858519
prp145 factor: 3086738052874713820874549933717582214781225298045359168326158870732152354004799186001213497885674888645553670120049637265198384203178998961805669[/code]


Sieving of 7^263-4^263 (GNFS 221.8, SNFS 222.3) is in progress.[/QUOTE]By the way, please could you send reports of your factorizations of homogeneous Cunninghams by email to me at [email]paul@leyland.vispa.com[/email] when you find them?

They are [b]much[/b] less likely to be overlooked when I prepare updated tables. This one, for instance, failed to get into the previous update.

Thanks,
[INDENT]Paul[/INDENT]

ACK, I'll send a mail next time.
7^263-4^263 was reserved about 41 days ago.

Update posted
 

The latest updated table have just been posted.

Paul

This bears repeating: Do your own ECM on these numbers. Even if they have been on the ECMNet server for a few months, do not assume that p40 factors have been ruled out. If you're going to do the smaller ones, smaller than SNFS 160 or GNFS 130, you're covered, but beyond that you should handle your own ECM needs. The number of cycles required to pull 80% of the p45 factors out of these numbers is immense.

This used to be true with a far smaller number of candidates on the page than today, so it's probably more so now: do your own ECM before sieving a number.

On 3,2,496+ I'm running 17000 curves at 11e7.

Mersenneforum is not the place for reserving or submitting these numbers. Reserve at Tom Womack's page, then submit at that page when complete, and mail the results to Paul. Announce in this thread if you like, but out of consideration for Paul, Tom, and others working on these numbers, please help avoid the usual merry-go-round of mysterious submissions and lost factors: do everything through Tom's page. After you submit, it even has a nice reminder to e-mail the factors to Paul - like a thoughtful flight attendant in first class!

[QUOTE=FactorEyes;205651]This bears repeating: Do your own ECM on these numbers. Even if they have been on the ECMNet server for a few months, do not assume that p40 factors have been ruled out.[/QUOTE]As part of the update cycle I retire any factored numbers still in the ECMNet server. While there, I checked the B1 value currently being issued to clients. It is 11M. That is, a single test to p40 has been completed and it is part way through the p45 test. That a p38 was still waiting to be found is not at all surprising.

Paul