is 2 1261963 - 1
has 379889 decimal digits
takes 0.040 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L3521926B7722437Cdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26723.545868.6567%42184751560835650.57418.7583%24.119971.4019%2.7451%
PrimeNet2560.007662.5000%5500900000.00052.4411%0.008163.4154%0.9154%
GPU722600.121765.0000%5500340000.00030.9081%0.122065.3178%0.3178%
Difference+7+23.4241+3.6567%+4212975+156049565+0.5738+7.8502%+23.9979+6.0840%+6.0840%

Known prime factors (1 factor, 110.3 bits, 0.00873777% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1261963156249750075829683561188480257576934110.267619074212460387838475408868
22 × 3 × 11 × 17 × 23 × 41 × 59 × 97 × 14723 × 652741 × 5319211
2015-02-0665274153192111.366e+110.04170.0611

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-02-24T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.239%
2003-12-23T00:00:00eteov4_computers2000005000000---0.021--3.419%
2014-09-29T22:04:00Jocelyn LaroucheManual testing250860250860---0.012--1.373%
2015-02-06T11:29:00mikrMSI42184751560835651234110.2670.5740.0801.1488.758%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-07-27T00:00:00ANONYMOUSv4_computers21256--0.008--
2001-11-10T00:00:00ANONYMOUSv4_computers21257--0.015--
2003-06-01T00:00:00ANONYMOUSv4_computers21258--0.030--
2022-03-07T17:32:04LordJuliusManual testing258260--0.091--
2009-02-14T18:24:00Sturle Sundeghini.ifi260261--0.122--
2011-05-09T14:41:00XyzzyManual testing261262--0.243--
2012-10-11T11:56:00dbaughManual testing262263--0.778--


ECM factoring results:

Old Calculation Method

Total ECM effort:19.240 GHz-days
Estimated T-Level:25.391
DigitsB1CurvesCompleteFacMiss
2011000301 / 1003.0104.855%
2550000301 / 2801.07534.064%
3025000050 / 6400.07892.479%

New Calculation Method

Total ECM effort:19.240 GHz-days
Estimated T-Level:25.391
DigitsB1CompleteFacMiss
201100012.2630.000%
25500001.33426.337%
302500000.11089.576%
3510000000.00799.255%


ECM Summary

B1B2factorcurvesGHz-days
5000050000002519.64
25000025000000509.60


Lucas-Lehmer results:
No L-L results for M1261963


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-29T20:11:36Oliver KruseGTX-0
1562497500758296835611884802575769
DCA82C87E5AEFD__no
2017-10-21T04:53:53kkmrkkblmbrbkc4.xlarge
1562497500758296835611884802575769
DCA82C87E5AEFD__no


P-1 factor-bounds graph:
B1 = 4218475, B2 = 156083565 (P-1 stage 2)
B1 = 4218475 (P-1 stage 1)
B1 = 200000, B2 = 5000000 (P-1 stage 2)
B1 = 250860 (P-1 stage 1)
B1 = 200000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
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TF factor-bounds graph:
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2100
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2120
Last modified: 2022-03-07T17:32:04+00:00