is 2 156241 - 1
has 47034 decimal digits
takes 0.001 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L9D2D8F5FF2234207double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual267190.180073.1343%10000000020000000000.975512.1123%191.155576.3884%3.2540%
PrimeNet2400.000055.0000%1700360000.000010.9640%0.000059.9338%4.9338%
GPU722440.000059.0909%2800550000.00007.4646%0.000062.1446%3.0537%
Difference+23+190.1800+14.0434%+99997200+1999945000+0.9754+4.6477%+191.1555+14.2438%+14.2438%

Known prime factors (1 factor, 88.3 bits, 0.05649366% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1562413722139676579528732955147992788.2661191153306935928704039
7 × 283 × 43951 × 530267 × 25800007
2009-01-1153026725800007666,864,2580.00910.0126

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-04-29T00:00:00ANONYMOUSv4_computers10000010000000---0.003--2.525%
2002-06-02T00:00:00ANONYMOUSv4_computers327683276800---0.001--1.426%
2002-07-20T00:00:00ANONYMOUSv4_computers655366553600---0.002--2.069%
2003-02-09T00:00:00ANONYMOUSv4_computers13107213107200---0.004--2.840%
2003-10-08T00:00:00ANONYMOUSv4_computers26214426214400---0.008--3.729%
2016-12-17T01:24:39kkmrkkblmbrbkManual testing100000000200000000012-
skipped known factor: 372213967657952873295514799
--0.975--12.112%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-11-04T00:00:00ANONYMOUSv4_computers252253--0.004--
2000-05-05T00:00:00ANONYMOUSv4_computers21254--0.015--
2022-03-07T03:54:01LordJuliusManual testing254255--0.015--
2001-01-08T00:00:00ANONYMOUSv4_computers21256--0.061--
2002-07-14T00:00:00ANONYMOUSv4_computers21257--0.123--
2022-03-07T03:54:01LordJuliusManual testing257258--0.123--
2008-12-31T15:33:00Sturle Sundegooch.ifi258259--0.246--


ECM factoring results:

Old Calculation Method

Total ECM effort:12.005 GHz-days
Estimated T-Level:29.750
DigitsB1CurvesCompleteFacMiss
2011000884 / 1008.8400.014%
2550000884 / 2803.1574.231%
30250000608 / 6400.95038.645%
3510000009 / 15660.00699.427%

New Calculation Method

Total ECM effort:12.005 GHz-days
Estimated T-Level:29.750
DigitsB1CompleteFacMiss
201100066.5700.000%
25500009.7190.006%
302500001.04035.348%
3510000000.08891.614%
4030000000.00699.395%


ECM Summary

B1B2factorcurvesGHz-days
10.00000e+0
5000050000002760.960
2500002500000059910.42
100000010000000090.626


Lucas-Lehmer results:
No L-L results for M156241


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-21T23:27:15Oliver KruseOllaptop
372213967657952873295514799
6F2C699845CEA2__no
2017-09-22T10:03:06Oliver KruseManual testing
372213967657952873295514799
6F2C699845CEA2__no
2017-10-11T23:00:32kkmrkkblmbrbkc4.xlarge6F2C699845CEA2__no
2020-04-17T17:49:08Oliver KruseAddPrpType5
372213967657952873295514799
57ED0F8876597D__no


P-1 factor-bounds graph:
B1 = 100000000, B2 = 2000000000 (P-1 stage 2)
B1 = 100000000 (P-1 stage 1)
B1 = 262144, B2 = 26214400 (P-1 stage 2)
B1 = 131072, B2 = 13107200 (P-1 stage 2)
B1 = 100000, B2 = 10000000 (P-1 stage 2)
B1 = 65536, B2 = 6553600 (P-1 stage 2)
B1 = 262144 (P-1 stage 1)
B1 = 32768, B2 = 3276800 (P-1 stage 2)
B1 = 131072 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
B1 = 65536 (P-1 stage 1)
B1 = 32768 (P-1 stage 1)
103
104
105
106
107
108
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
267
259
258
257
256
255
254
253
250
260
270
280
290
2100
Last modified: 2022-03-07T03:54:01+00:00