is 2 281243 - 1
has 84663 decimal digits
takes 0.002 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LB8AC738B9F20F330double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual267105.652171.6418%262144262144000.01664.0288%105.668772.7843%1.1425%
PrimeNet2400.000052.5000%3000800000.000115.0211%0.000159.6350%7.1350%
GPU722440.000056.8182%50001300000.000110.8462%0.000161.5018%4.6836%
Difference+23+105.6521+14.8236%+257144+26084400+0.0165-6.8175%+105.6686+11.2825%+11.2825%

Known prime factors (2 factors, 156.4 bits, 0.05559754% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
28124310479232684683007326472269.8281863021068023561
1863021068023561
2008-10-0111863021068023561430.111,005,7211,878,407
2812431121980476096423864402849592786.536199468160291353716253
31 × 9059 × 32441 × 21894619177
2020-06-013244121894619177104,364,49411.82022.075

1 Composite Factors:
exponentprime factorscomposite factordigitsbits*
28124311757494476685846580698081771817695661515435647348156.364
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-04-29T00:00:00ANONYMOUSv4_computers500001000000---0.001--1.364%
2001-04-29T00:00:00ANONYMOUSv4_computers1000004000000---0.003--2.286%
2001-06-30T00:00:00ANONYMOUSv4_computers10000010000000---0.006--2.760%
2002-06-09T00:00:00ANONYMOUSv4_computers327683276800---0.002--1.586%
2003-03-16T00:00:00ANONYMOUSv4_computers13107213107200---0.008--3.094%
2003-11-28T00:00:00ANONYMOUSv4_computers26214426214400---0.017--4.029%
2006-01-15T00:00:00Jocelyn Larouchev4_computers281243281243---0.003--1.134%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-11-24T00:00:00ANONYMOUSv4_computers252253--0.002--
2000-05-05T00:00:00ANONYMOUSv4_computers21254--0.009--
2022-03-07T06:11:32LordJuliusManual testing254255--0.009--
2001-02-25T00:00:00ANONYMOUSv4_computers21256--0.034--
2002-03-16T00:00:00ANONYMOUSv4_computers21257--0.068--
2004-02-07T00:00:00ANONYMOUSv4_computers21258--0.137--


ECM factoring results:

Old Calculation Method

Total ECM effort:8.935 GHz-days
Estimated T-Level:26.453
DigitsB1CurvesCompleteFacMiss
2011000464 / 1004.6400.943%
2550000464 / 2801.65719.012%
30250000186 / 6400.29174.763%

New Calculation Method

Total ECM effort:8.935 GHz-days
Estimated T-Level:26.453
DigitsB1CompleteFacMiss
201100024.4680.000%
25500003.0674.656%
302500000.29474.559%
3510000000.02397.768%
4030000000.00199.856%


ECM Summary

B1B2factorcurvesGHz-days
10.00000e+0
5000050000002782.032
250000250000001425.190
25000025000000230.841
2500002850000070.268
25000038500000140.604


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2002-03-03T00:00:00ANONYMOUSv4_computersB8AC738B9F20F3300.002


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-22T11:37:27Oliver KruseOllaptop
1047923268468300732647
229422F9FDDC4B__no
2017-09-22T20:36:07Oliver KruseManual testing
1047923268468300732647
229422F9FDDC4B__no
2017-10-13T05:30:55kkmrkkblmbrbkc4.xlarge229422F9FDDC4B__no
2020-04-17T21:19:10Oliver KruseAddPrpType5
1047923268468300732647
6BAE1046DF010C__no
2020-06-01T04:09:06CrypticCluecruncher
1047923268468300732647
112198047609642386440284959
6BAE1046DF010CDEno


P-1 factor-bounds graph:
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 = 100000, B2 = 4000000 (P-1 stage 2)
B1 = 281243 (P-1 stage 1)
B1 = 262144 (P-1 stage 1)
B1 = 32768, B2 = 3276800 (P-1 stage 2)
B1 = 131072 (P-1 stage 1)
B1 = 50000, B2 = 1000000 (P-1 stage 2)
B1 = 100000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 32768 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2022-05-09T05:51:18+00:00