is 2 2050481 - 1
has 617257 decimal digits
takes 0.135 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L3A32E10E463B1ABCdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26714.491268.6567 %500000150000000.12305.1384 %14.614270.2673 %
Target2620.299666.1290 %90006000000.00391.3304 %0.303566.5796 %
Difference+5+14.1916+2.5277 %+491000+14400000+0.1191+3.8081%+14.3106+3.6876 %

Known prime factors (1 factor, 82.5 bits, 0.00402555% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
205048170459279472184738496544412582.5431718115882863209620
22 × 3 × 5 × 7 × 997 × 363901 × 11275213
2015-10-0636390111275213694,8020.09140.1094

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2003-02-24ANONYMOUSv4_computers204820480012--0.0010.765%
2006-01-15Jossv4_computers40004000--0.0000.174%
2009-05-12Rob_Deetwopc20000280000--0.0032.147%
2010-12-26JossManual testing3000030000--0.0030.924%
2011-01-04JossManual testing5000050000--0.0051.259%
2011-01-26James Heinrichi7-92013500028687506--0.0275.250%
2014-10-22JossManual testing166302166302--0.0162.305%
2015-10-06Bruno Victal5820K.ECM500000150000001222582.5430.1078.207%
2016-03-17alpertronManual testing5000001500000012
skipped known factor: 7045927947218473849654441
---8.207%


Trial Factoring results:
5758596061626364656667
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
1999-01-10slaurv4_computers212580.019
2022-03-09LordJuliusManual testing21260
2009-01-02Sturle Sundegopher.ifi2602610.075
2012-03-09Sebastian HornbostelManual testing2612620.150
2013-09-01ramgeisManual testing2622630.479
2015-04-13VictordeHollanderManual testing2632652.780


ECM factoring results:
Total ECM effort:80.859 GHz-days
Estimated T-Level:25.390
DigitsB1CompleteFacMiss
201100011.8270.001%
25500001.17330.939%
302500000.07892.496%
3510000000.00499.620%


ECM Summary

B1B2factorcurvesGHz-days
5000050000502.204
500005000000181.326
50000672365370.588
500006750000141.179
500006900000141.191
682076005422515074.37


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-02-14slaurv4_computers3A32E10E463B1ABC0.135


PRP results:
dateuseridcompidcofactorsres64
2017-09-30alpertronManual testing
7045927947218473849654441
2E87AA5B1AB8F17B
2017-10-21Oliver KruseThreadripper-PC
7045927947218473849654441
2E87AA5B1AB8F17B


CERT results:
No CERT results for M2050481


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
B1 = 135000, B2 = 2868750 (P-1 stage 2)
B1 = 166302 (P-1 stage 1)
B1 = 135000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 20000, B2 = 280000 (P-1 stage 2)
B1 = 30000 (P-1 stage 1)
B1 = 20000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 4000 (P-1 stage 1)
B1 = 2048 (P-1 stage 1)
102
103
104
105
106
102
103
104
105
106
107
108
TF factor-bounds graph:
265
263
262
261
260
258
this exponent TF target: 62
TF double-checked to: 67
ECM T-Level=25.39 ~= 68-bit
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Last modified: 2024-03-13T02:15:48+00:00