is 2 5250281 - 1
has 1580493 decimal digits
takes 0.829 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-LF334ED4040FEEB6Edouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26811.352766.1765 %31500092137500.18314.4975 %11.535867.6977 %
Target2662.812965.1515 %3000030000000.04391.9905 %2.856865.8452 %
Difference+2+8.5398+1.0250 %+285000+6213750+0.1392+2.5070%+8.6790+1.8525 %

Known prime factors (1 factor, 111.4 bits, 0.00212128% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
5250281336245633242935114697619962633280934111.373320216797198983363650078884
22 × 7 × 41 × 4421 × 13093 × 13183 × 59239 × 6170503
2019-03-275923961705032.875e+100.08980.1438

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2001-01-08ANONYMOUSv4_computers1500015000--0.0030.352%
2009-10-13USAFSSP4_2600600009750006--0.0282.628%
2019-03-27USAFSS6917th_Scty_Sq315000921375012234111.3730.1835.488%


Trial Factoring results:
575859606162636465666768
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1998-06-01MadPoov4_computers212620.059
2009-06-09GrunwalderGIMPManual testing2622630.187
2014-12-19VictordeHollanderManual testing2632651.086
2015-08-12snme2pm1Manual testing2652661.423
2016-06-03Gordon SpenceManual testing2662672.847
2018-06-17ramgeisManual testing2672685.693


ECM factoring results:
Total ECM effort:2.161 GHz-days
Estimated T-Level:1.731
DigitsB1CompleteFacMiss
20110000.34670.740%
25500000.03296.848%
302500000.00299.798%


ECM Summary

B1B2factorcurvesGHz-days
50000500000092.161


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-08-16ANONYMOUSv4_computersF334ED4040FEEB6E0.829
2001-02-11ANONYMOUSv4_computersF334ED4040FEEB6E0.829


PRP results:
dateuseridcompidcofactorsres64
2019-03-28_p95holder_TFL16_PRPt11-E_b
3362456332429351146976199626332809
97E13ECE106F3B19
2019-03-30arnaudstm-11-010
3362456332429351146976199626332809
97E13ECE106F3B19


CERT results:
No CERT results for M5250281


P-1 factor-bounds graph:
B1 = 315000, B2 = 9213750 (P-1 stage 2)
B1 = 315000 (P-1 stage 1)
B1 = 60000, B2 = 975000 (P-1 stage 2)
B1 = 60000 (P-1 stage 1)
B1 = 15000 (P-1 stage 1)
103
104
105
106
103
104
105
106
107
TF factor-bounds graph:
268
267
266
265
263
262
this exponent TF target: 66
TF double-checked to: 67
ECM T-Level=1.73 ~= -11-bit
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Last modified: 2024-03-13T02:15:48+00:00