is 2 42219521 - 1
has 12709343 decimal digits
takes 62.230 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-LC588AFC1EA139FC7double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual27345.307164.3836 %35500064787501.47183.3420 %46.778965.5739 %
Target27222.651563.8889 %300000450000005.84623.8711 %28.497665.2868 %
Difference+1+22.6557+0.4947 %+55000-38521250-4.3744-0.5290 %+18.2813+0.2871 %

Known prime factors (1 factor, 86.0 bits, 0.00020365% known):
Remaining cofactor is PRP status unknown

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
42219521763333493468520905173757212685.981904005392989324660
22 × 5 × 123631 × 339749 × 1076107
2018-08-283397491076107242,6390.81191.4778

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2008-07-04curtiscv4_computers630000630000--1.3461.964%
2018-08-28Architects Cubedgpu7235500064787501222685.9811.4723.703%


Trial Factoring results:
5758596061626364656667686970717273
 BitsFactor
dateuseridcompidfromtofactorbits*digitsGHz-days
2007-06-15Geoff Wingv4_computers212691.416
2015-01-19Architects CubedManual testing2692702.832
2015-03-18Mark RoseManual testing2702715.664
2015-08-30AirSquirrelsManual testing27127211.33
2018-08-11ANONYMOUSManual testing27227322.66


ECM factoring results:
No ECM results for M42219521


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2008-08-07curtiscv4_computersC588AFC1EA139FC762.23
2017-12-23Mark RoserocksteadyC588AFC1EA139FC764.44


PRP results:
No PRP results for M42219521


CERT results:
No CERT results for M42219521


P-1 factor-bounds graph:
B1 = 355000, B2 = 6478750 (P-1 stage 2)
B1 = 630000 (P-1 stage 1)
B1 = 355000 (P-1 stage 1)
104
105
106
104
105
106
107
TF factor-bounds graph:
273
272
271
270
269
this exponent TF target: 72
TF double-checked to: 67
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Last modified: 2024-03-13T02:15:48+00:00