is 2 256579 - 1
has 77238 decimal digits
takes 0.002 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
-unknown- primality tests remaining
ResidueStatus
L-L-unknown--unknown-
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actualunknown30000000100358126969105,417.947373.0290%5,417.947373.0290%73.0290%
PrimeNet2400.000055.0000%2600700000.000114.2582%0.000161.4162%6.4162%
GPU722440.000059.0909%45001100000.000110.2010%0.000163.2640%4.1731%
Difference-440.0000-59.0909%+29995500+10035812586910+5,417.9472+62.8280%+5,417.9472+9.7650%+9.7650%

Known prime factors (3 factors, 191.1 bits, 0.07446712% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
25657973648436171032.77814352
24 × 3 × 13 × 23
-16232.467e-91.623e-73.226e-7
25657920590868475660114976732270.8024012578674727884
22 × 5897 × 39019 × 4359697
2016-03-113901943596971,279.10.00270.0044
2565792167976679973084227347061192787.486422477420204514833121
3 × 1231 × 114399518062419397
2022-05-141231114399518062419397149,682,08861,756,673115,344,267

4 Composite Factors:
exponentprime factorscomposite factordigitsbits*
2565791516485262614519176478560440324132103.581
256579159668092133046211035803804488799242337120.264
25657944640522675624057741051950292828520577070736108748158.289
25657932877046848711360314582589497953941064759256738765
06131679
58191.067
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2021-09-08T17:08:00Oliver KruseOllaptop30000000300000000024-
skipped known factor: 7364843617
skipped known factor: 2059086847566011497673
--1.901--44.071%
2022-04-27T23:27:09Oliver KruseThreadripper-PC3000000010035812696910-
skipped known factor: 7364843617
skipped known factor: 2059086847566011497673
--5,418--63.174%


Trial Factoring results:
No TF results for M256579


ECM factoring results:

Old Calculation Method

Total ECM effort:12.027 GHz-days
Estimated T-Level:27.102
DigitsB1CurvesCompleteFacMiss
2011000550 / 1005.5000.398%
2550000550 / 2801.96413.976%
30250000269 / 6400.42065.663%

New Calculation Method

Total ECM effort:12.027 GHz-days
Estimated T-Level:27.102
DigitsB1CompleteFacMiss
201100035.5800.000%
25500004.8260.802%
302500000.48661.492%
3510000000.03996.192%
4030000000.00399.745%


ECM Summary

B1B2factorcurvesGHz-days
5000050000002061.501
500005000000750.547
250000250000002278.271
2500002500000070.255
2500003426631070.286
2500003475000070.288
25000035105348140.579
2500003850000070.301


Lucas-Lehmer results:
No L-L results for M256579


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-22T07:51:36Oliver KruseOllaptop
7364843617
2059086847566011497673
8FE6D6857867D6__no
2017-09-22T10:06:38Oliver KruseManual testing
7364843617
2059086847566011497673
8FE6D6857867D6__no
2017-10-12T17:10:11Oliver KruseGTX-08FE6D6857867D6__no
2017-11-06T16:27:21kkmrkkblmbrbkc4.xlarge
7364843617
2059086847566011497673
8FE6D6857867D6__no
2020-04-17T20:17:28Oliver KruseAddPrpType5
7364843617
2059086847566011497673
076AD6CA81ED6E__no
2022-05-14T22:41:45aperson12012_VP113
7364843617
2059086847566011497673
216797667997308422734706119
076AD6CA81ED6E61no


P-1 factor-bounds graph:
B1 = 30000000, B2 = 10035812696910 (P-1 stage 2)
B1 = 30000000, B2 = 3000000000 (P-1 stage 2)
B1 = 30000000 (P-1 stage 1)
100
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103
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108
100
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102
103
104
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109
1010
1011
1012
1013
1014
1015
1016
1017
1018
TF factor-bounds graph:
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290
2100
Last modified: 2022-07-26T14:09:10+00:00