is 2 15186331 - 1
has 4571542 decimal digits
takes 7.616 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L545C5BF5C4254834double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual27262.973366.6667%17500024937500.21912.3271%63.192567.4424%
Target2697.861565.2174%100000208000000.89292.9988%8.754366.2604%
Difference+3+55.1119+1.4493%+75000-18306250-0.6737-0.6717%+54.4381+1.1819%

Known prime factors (1 factor, 78.3 bits, 0.00051528% known):
Remaining cofactor is PRP status unknown

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
151863313599025224579480603316072478.25211849554789038513
36 × 359 × 13633 × 3321151
2023-03-301363333211514,373.90.14100.2458

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2002-06-29ANONYMOUSv4_computers1750002493750---0.219--2.327%


P+1 Factoring results:
dateuseridcompidb1b2startfactorSmoothdigitsbits*ghz-days
2023-03-30ATHec2-P_110000002900000027P-12478.2522.193


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2000-12-31Net_Forcev4_computers21257--0.001--
2001-01-08Net_Forcev4_computers21258--0.003--
2001-02-04ANONYMOUSv4_computers21265--0.480--
2013-09-16David CampeauManual testing265266--0.492--
2014-05-14NesowaManual testing266267--0.984--
2017-12-29ramgeisManual testing267268--1.968--
2017-12-29ramgeisManual testing268269--3.937--
2021-07-06lycornManual testing269270--7.873--
2021-09-03LaurVGPU72_TF270271--15.75--
2021-10-10-Anonymous-Manual testing271272--31.49--


ECM factoring results:
Total ECM effort:0.763 GHz-days
Estimated T-Level:0.192
DigitsB1CompleteFacMiss
20110000.03896.227%
25500000.00499.645%


ECM Summary

B1B2factorcurvesGHz-days
50000500000010.763


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2003-04-27ANONYMOUSv4_computers545C5BF5C42548347.616
2005-09-22ANONYMOUSv4_computers545C5BF5C42548347.616


PRP results:
No PRP results for M15186331


P-1 factor-bounds graph:
B1 = 1000000, B2 = 29000000 (P-1 stage 2)
B1 = 1000000 (P-1 stage 1)
B1 = 175000, B2 = 2493750 (P-1 stage 2)
B1 = 175000 (P-1 stage 1)
103
104
105
106
103
104
105
106
107
108
TF factor-bounds graph:
272
271
270
269
268
267
266
265
258
257
this exponent TF target: 69
TF double-checked to: 67.8
ECM T-Level=0.19 ~= -16-bit
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270
280
Last modified: 2023-06-05T21:50:05+00:00