is 2 15195757 - 1
has 4574379 decimal digits
takes 7.621 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-L623D75479C6D081Edouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual27262.934366.6667%17500024937500.21912.3273%63.153467.4424%
Target2697.856665.2174%100000208000000.89292.9990%8.749566.2605%
Difference+3+55.0777+1.4493%+75000-18306250-0.6737-0.6717%+54.4039+1.1819%

Known prime factors (1 factor, 99.4 bits, 0.00065402% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
151957578267493264829410615623477608393099.38327203295185719969777167
3 × 7 × 10789 × 36497 × 561733 × 5856443
2023-04-1756173358564431.050e+100.61830.8314

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2002-06-29ANONYMOUSv4_computers1750002493750---0.219--2.327%
2002-12-25Team Prime Ribv4_computers1750002493750---0.219--2.327%


P+1 Factoring results:
dateuseridcompidb1b2startfactorSmoothdigitsbits*ghz-days
2023-04-17ATHec2-P_110000002900000027P-13099.3832.193


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2000-12-31Net_Forcev4_computers21257--0.001--
2001-01-08Net_Forcev4_computers21258--0.003--
2001-01-28MadPoov4_computers21265--0.480--
2014-05-14NesowaManual testing265266--0.492--
2014-05-14NesowaManual testing266267--0.984--
2016-11-02mikrManual testing267268--1.967--
2017-10-11ramgeisManual testing268269--3.934--
2021-07-06lycornManual testing269270--7.868--
2021-09-06SRBaseManual testing270271--15.74--
2021-10-15-Anonymous-Manual testing271272--31.47--


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)
2002-08-31Team Prime Ribv4_computers623D75479C6D081E7.621
2003-12-31ANONYMOUSv4_computers623D75479C6D081E7.621


PRP results:
dateuseridcompidcofactorsres64PRP
2023-04-18Naegi Makoto5950X
826749326482941061562347760839
A278A392BA26F906no
2023-05-21recluxs4
826749326482941061562347760839
A278A392BA26F906no


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)
104
105
106
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
250
260
270
280
290
2100
Last modified: 2023-06-05T21:50:05+00:00