Gratuitous factors thread

[jrk]

Originally Posted by schickel

sigma: -722316553

ECMNET bug? I assume that should be sigma 3572650743, which gives the expected G.O.

[schickel]

Originally Posted by jrk

ECMNET bug? I assume that should be sigma 3572650743, which gives the expected G.O.

Don't know....that's what's in the client log files, too. (Older v2.0 client & server.)

[JoeCrump]

Add 2^32 to the negative sigma reported

2^32 - 722316553 = 3572650743

ECM is most likely using signed output instead of unsigned.

[jrk]

Originally Posted by JoeCrump

ECM is most likely using signed output instead of unsigned.

gmp-ecm outputs the correct sigma; that's why I asked if the bug is in ECMNET.

[xilman]

Input number is
2042051595552167746342275079282861934041894421970170292986619401704995990393201835195760054314326317193473094974797857477411452836226028388537276799396967606930799257964059012665415448668778781955310866521469996957438292583207092410688568727873146367564496256594721369162389899152496702871167970005716153438542407811915318199016780403936746140815792039082359742869614309311963768190545218508723545325008681845008691762523763189358179859828747758283470083 (454 digits)
Using B1=1000000000, B2=197713677773176, polynomial x^1, x0=1810143575
Step 1 took 4888481ms
Step 2 took 88506ms
********** Factor found in step 2:
60120920503954047277077441080303862302926649855338567
Found probable prime factor of 53 digits:
60120920503954047277077441080303862302926649855338567
Composite cofactor
33965740684523710874897792701030029397475834554589979746672229046534924730254495631455594163183667853625804071804093552244856489012272119518848037153284265550709551421022718202298577995035871375614477994821102904627773266600230258907915766604009878901818010027742994123164599456633866771429281907869168498625224044196962920910514628612751337070878684659117684938855714799122639747803764872032894510949 has 401 digits
Report your potential champion to Paul Zimmermann <zimmerma@loria.fr>
(see http://www.loria.fr/~zimmerma/records/Pplus1.html)

This one will make second place on Paul's table when he updates it. It is a factor of GW(5,682).

A p46 has also been reported and should be placed tenth. Two p45 will drop out.

Paul

[akruppa]

Amazingly smooth order. Nice one!

[Andi_HB]

10^245-9 splits into p70*p73
Thats my biggest GNFS Number till now.

Number: c143
N = 14666309992949100354751067452740459698631568586537981928590377727072933726554922007034652454528707698510506083768049331589810208591678421415597 (143 digits)
Divisors found:
r1=6858031324105906934531379371908179531888297486893109903873924200917601 (pp70)
r2=2138559784846297975822122362999433744698609346939040015198735671284328397 (pp73)
Version: Msieve v. 1.48
Total time: 422.16 hours.
Factorization parameters were as follows:
n: 14666309992949100354751067452740459698631568586537981928590377727072933726554922007034652454528707698510506083768049331589810208591678421415597
# norm 8.472133e-014 alpha -7.793035 e 1.468e-011 rroots 3
Y0: -3427708690350665253071870200
Y1: 6735015903598187
c0: 307063674198654785265461319769605471
c1: 3401953667000316550513538395863
c2: -1025164364553989554645487
c3: -1202299680638206019
c4: -156909176264
c5: 30996
skew: 2964823.76
type: gnfs
Factor base limits: 14300000/14300000
Large primes per side: 3
Large prime bits: 28/28
Sieved algebraic special-q in [0, 0)
Total raw relations: 23948228
Relations: 3816522 relations
Pruned matrix : 2380394 x 2380619
Polynomial selection time: 0.00 hours.
Total sieving time: 402.71 hours.
Total relation processing time: 0.40 hours.
Matrix solve time: 15.61 hours.
time per square root: 3.45 hours.
Prototype def-par.txt line would be: gnfs,142,5,65,2000,1e-05,0.28,250,20,50000,3600,14300000,14300000,28,28,56,56,2.5,2.5,100000
total time: 422.16 hours.
x86 Family 6 Model 23 Stepping 6, GenuineIntel
Windows-Vista-6.0.6002-SP2
processors: 2, speed: 2.09GHz

[Batalov]

Another boring nice split in alq(189840,2265):
p62 factor: 12961759727371308543387311443052649710907049967165731692947329
p62 factor: 20047877404113732085125573515760431677677380364808836826997953

[unconnected]

From 980820:i598
----
Using B1=3000000, B2=5706890290, polynomial Dickson(6), sigma=2467788292
Step 1 took 39795ms
Step 2 took 18930ms
********** Factor found in step 2: 4638975611799409418990318035605789048108742092301
Found probable prime factor of 49 digits: 4638975611799409418990318035605789048108742092301
Probable prime cofactor 153953786053497927655688111379214112675519921430120508574221638996640451177539 has 78 digits

[Uncwilly]

Originally Posted by unconnected

Found probable prime factor of 49 digits: 4638975611799409418990318035605789048108742092301
Probable prime cofactor 153953786053497927655688111379214112675519921430120508574221638996640451177539 has 78 digits

I ran both of those through Dario's applet and they are both prime.

[Batalov]

109 doesn't belong to A063684
because 2+109! is now FF and has five prime factors (hence, its mu is -1)

Input number is (2+109!)/680228282 (168 digits)
Using B1=11000000, B2=58553269330, polynomial Dickson(12), sigma=3745215087
Step 1 took 28241ms
Step 2 took 17979ms
********** Factor found in step 2: 3155245204619274806183912472903834871504857098057
Found probable prime factor of 49 digits: 3155245204619274806183912472903834871504857098057
Probable prime cofactor ((2+109!)/680228282)/3155245204619274806183912472903834871504857098057 has 119 digits