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
factored, 0 LL tests remaining
ResidueStatus
L-LB8AC738B9F20F330double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual267105.652171.6418 %1875000105911133905.735011.6142 %111.387174.9354 %
Target2440.000056.8182 %50006500000.000410.8462 %0.000461.5018 %
Difference+23+105.6521+14.8236 %+1870000+10590463390+5.7346+0.7680%+111.3867+13.4336 %

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:
P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2001-04-29ANONYMOUSv4_computers500001000000--0.00118.386%
2001-04-29ANONYMOUSv4_computers1000004000000--0.00322.737%
2001-06-30ANONYMOUSv4_computers10000010000000--0.00625.162%
2002-06-09ANONYMOUSv4_computers32768327680012--0.00220.960%
2003-03-16ANONYMOUSv4_computers1310721310720030--0.00826.162%
2003-11-28ANONYMOUSv4_computers2621442621440012--0.01728.687%
2006-01-15Jossv4_computers281243281243--0.00314.761%
2023-12-09USAFSS6917th_Scty_Sq187500010591113390--5.85245.721%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1999-11-24ANONYMOUSv4_computers2522530.002
2000-05-05ANONYMOUSv4_computers212540.009
2022-03-07LordJuliusManual testing254255
2001-02-25ANONYMOUSv4_computers212560.034
2002-03-16ANONYMOUSv4_computers212570.068
2004-02-07ANONYMOUSv4_computers212580.137


ECM factoring results:
Total ECM effort:80.072 GHz-days
Estimated T-Level:29.983
DigitsB1CompleteFacMiss
201100060.2400.000%
25500009.1990.010%
302500000.99736.911%
3510000000.08491.934%
4030000000.00699.427%


ECM Summary

B1B2factorcurvesGHz-days
10.019
5000050000002782.018
250000250000001495.485
25000025000000230.858
2500002850000070.273
2500003350000070.291
25000036750000281.208
25000038500000140.622
25000055133578522769.30


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


PRP results:
dateuseridcompidcofactorsres64
2017-09-22Oliver KruseOllaptop
1047923268468300732647
229422F9FDDC4B11
2017-09-22Oliver KruseManual testing
1047923268468300732647
229422F9FDDC4B11
2017-10-13kkmrkkblmbrbkc4.xlarge
1047923268468300732647
229422F9FDDC4B11
2020-04-17Oliver KruseAddPrpType5
1047923268468300732647
6BAE1046DF010CDE
2020-06-01M Millercruncher
1047923268468300732647
112198047609642386440284959
6BAE1046DF010CDE


CERT results:
No CERT results for M281243


P-1 factor-bounds graph:
B1 = 1875000, B2 = 10591113390 (P-1 stage 2)
B1 = 1875000 (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 = 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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107
100
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105
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109
1010
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1016
TF factor-bounds graph:
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257
256
255
254
253
this exponent TF target: 44
TF double-checked to: 67
ECM T-Level=29.98 ~= 83-bit
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Last modified: 2024-03-13T02:15:48+00:00