is 2 15152857 - 1
has 4561465 decimal digits
takes 7.600 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L423FD11C46324FA6double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual27263.112466.6667%18500044400000.30312.6879%63.415667.5626%
Target2697.878865.2174%10000026000000.17182.9978%8.050666.2601%
Difference+3+55.2336+1.4493%+85000+1840000+0.1313-0.3099%+55.3649+1.3025%

Known prime factors (1 factor, 73.6 bits, 0.00048540% known):
Remaining cofactor is PRP status unknown

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
15152857138475639312648995162972373.552456929143172964
22 × 32 × 7 × 11 × 37 × 3079 × 1446919
2022-11-2230791446919151.490.05940.1071

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2002-04-20ANONYMOUSv4_computers1850004440000---0.303--2.688%


P+1 Factoring results:
dateuseridcompidb1b2startfactorSmoothdigitsbits*ghz-days
2022-11-22ATHec2-P_110000002900000027P-12373.5522.193


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2000-12-31Net_Forcev4_computers21257--0.001--
2000-12-31Net_Forcev4_computers21258--0.003--
2001-04-29ANONYMOUSv4_computers21265--0.481--
2016-03-16Mark RoseManual testing265266--0.493--
2014-05-14NesowaManual testing266267--0.986--
2017-12-24ramgeisManual testing267268--1.973--
2017-12-24ramgeisManual testing268269--3.945--
2021-06-30lycornManual testing269270--7.891--
2021-09-02SRBaseManual testing270271--15.78--
2021-10-10-Anonymous-Manual testing271272--31.56--


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)
2002-04-28ANONYMOUSv4_computers35B4308D1BF197877.600
2006-09-04ANONYMOUSv4_computers423FD11C46324FA67.600
2006-10-01mikaelv4_computers423FD11C46324FA67.600


PRP results:
No PRP results for M15152857


P-1 factor-bounds graph:
B1 = 1000000, B2 = 29000000 (P-1 stage 2)
B1 = 1000000 (P-1 stage 1)
B1 = 185000, B2 = 4440000 (P-1 stage 2)
B1 = 185000 (P-1 stage 1)
102
103
104
105
106
102
103
104
105
106
107
108
TF factor-bounds graph:
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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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280
Last modified: 2023-04-26T21:34:10+00:00