is 2 18851141 - 1
has 5674759 decimal digits
takes 12.018 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L992786917EFCB844double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual27012.675764.2857 %33800096470000.78134.4041 %13.456965.8586 %
Target2696.333163.7681 %130000180000001.02013.4761 %7.353365.0276 %
Difference+1+6.3425+0.5176 %+208000-8353000-0.2389+0.9280%+6.1036+0.8310 %

Known prime factors (1 factor, 70.9 bits, 0.00037617% known):
Remaining cofactor is PRP status unknown

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1885114122227025874442466920412270.91358954059795220
22 × 5 × 19 × 37463 × 4141213
2020-10-1937463414121316.4100.24130.3895

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2003-04-19ANONYMOUSv4_computers270000270000--0.2501.713%
2020-10-19James Heinrich3930K33800096470001222270.9130.7934.864%


Trial Factoring results:
5758596061626364656667686970
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2001-10-20Net_Forcev4_computers212580.002
2001-12-08Net_Forcev4_computers212590.002
2002-03-31Team Prime Ribv4_computers212660.396
2002-11-09ANONYMOUSv4_computers212660.396
2014-08-02NesowaManual testing2662670.793
2017-10-20YxinityManual testing2672681.586
2017-10-27ramgeisManual testing2682693.171
2020-01-19lycornManual testing2692706.343


ECM factoring results:
Total ECM effort:0.925 GHz-days
Estimated T-Level:0.192
DigitsB1CompleteFacMiss
20110000.03896.227%
25500000.00499.645%


ECM Summary

B1B2factorcurvesGHz-days
50000500000010.925


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2003-06-17ANONYMOUSv4_computers992786917EFCB84412.02
2007-05-28ANONYMOUSv4_computers992786917EFCB84412.02


PRP results:
No PRP results for M18851141


CERT results:
No CERT results for M18851141


P-1 factor-bounds graph:
B1 = 338000, B2 = 9647000 (P-1 stage 2)
B1 = 338000 (P-1 stage 1)
B1 = 270000 (P-1 stage 1)
103
104
105
106
103
104
105
106
107
TF factor-bounds graph:
270
269
268
267
266
259
258
this exponent TF target: 69
TF double-checked to: 67
ECM T-Level=0.19 ~= -16-bit
250
260
270
280
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Last modified: 2024-03-13T02:15:48+00:00