is 2 245251 - 1
has 73828 decimal digits
takes 0.001 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LF82516A42B5005F2double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual267121.157273.1343%12200000050214212848802,226.823024.1971%2,347.980279.6350%
Target2440.000059.0909%45005500000.000310.1302%0.000363.2351%
Difference+23+121.1572+14.0434%+121995500+5021420734880+2,226.8227+14.0669%+2,347.9799+16.3999%

Known prime factors:
No known factors for M245251

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-06-09ANONYMOUSv4_computers10000010000000---0.005--2.704%
2002-06-02ANONYMOUSv4_computers327683276800---0.002--1.547%
2002-08-03ANONYMOUSv4_computers655366553600---0.003--2.226%
2003-03-07ANONYMOUSv4_computers13107213107200---0.007--3.034%
2003-10-31ANONYMOUSv4_computers26214426214400---0.014--3.957%
2011-02-04Jocelyn LaroucheManual testing20000002000000---0.016--2.594%
2011-07-24Jocelyn LaroucheManual testing20552312055231---0.017--2.620%
2012-02-26Jocelyn LaroucheManual testing25690382569038---0.021--2.836%
2013-10-12David Campeaui5-2500k261000075690000---0.054--6.384%
2014-12-18thelegendarymudkipi5-4670k10000000250000000---0.188--8.528%
2016-05-13mognutsManual testing274268550---5.14804e-5--0.134%
2019-04-13Alexhome100000000200000000012---1.656--12.513%
2022-06-02Sid & AndyMagic_8_Ball1220000005021421284880---2,227--24.197%


P+1 Factoring results:
dateuseridcompidb1b2startfactorSmoothdigitsbits*ghz-days
2023-02-05masserManual testing3000000096000000013747--0.775
2023-02-05masserManual testing3000000099000000027--0.788
2023-02-11masserManual testing3000000099000000065--0.788


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-11-24ANONYMOUSv4_computers252253--0.002--
2000-04-19ANONYMOUSv4_computers21254--0.010--
2022-03-07LordJuliusManual testing254255--0.010--
2001-02-18ANONYMOUSv4_computers21256--0.039--
2002-04-14ANONYMOUSv4_computers21257--0.078--
2016-02-23Mark RoseManual testing257258--0.078--
2008-12-31Sturle Sundeghini.ifi258259--0.157--
2009-01-24Sturle Sundekinner.ifi259260--0.313--
2013-07-15lycornasteroid260261--0.626--
2015-08-04snme2pm1Manual testing261262--1.253--
2016-01-21Gordon SpenceManual testing262263--4.003--
2016-01-21Gordon SpenceManual testing263264--8.005--
2018-03-11Gordon SpenceManual testing264265--15.23--
2019-12-30Gordon SpenceManual testing265266--30.47--


ECM factoring results:
Total ECM effort:19.161 GHz-days
Estimated T-Level:29.865
DigitsB1CompleteFacMiss
201100064.0280.000%
25500009.2430.010%
302500000.97337.791%
3510000000.08092.310%
4030000000.00599.466%


ECM Summary

B1B2factorcurvesGHz-days
5000050000002821.685
2500002500000058517.48


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1997-01-01Ken KieferF82516A42B5005F20.001
2016-06-01MadPooManual testingF82516A42B5005F20.001


PRP results:
No PRP results for M245251


P-1 factor-bounds graph:
B1 = 122000000, B2 = 5021421284880 (P-1 stage 2)
B1 = 100000000, B2 = 2000000000 (P-1 stage 2)
B1 = 122000000 (P-1 stage 1)
B1 = 100000000 (P-1 stage 1)
B1 = 10000000, B2 = 250000000 (P-1 stage 2)
B1 = 10000000 (P-1 stage 1)
B1 = 2610000, B2 = 75690000 (P-1 stage 2)
B1 = 2610000 (P-1 stage 1)
B1 = 2569038 (P-1 stage 1)
B1 = 2055231 (P-1 stage 1)
B1 = 2000000 (P-1 stage 1)
B1 = 262144, B2 = 26214400 (P-1 stage 2)
B1 = 131072, B2 = 13107200 (P-1 stage 2)
B1 = 100000, B2 = 10000000 (P-1 stage 2)
B1 = 65536, B2 = 6553600 (P-1 stage 2)
B1 = 262144 (P-1 stage 1)
B1 = 32768, B2 = 3276800 (P-1 stage 2)
B1 = 131072 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
B1 = 65536 (P-1 stage 1)
B1 = 32768 (P-1 stage 1)
B1 = 2742, B2 = 68550 (P-1 stage 2)
B1 = 2742 (P-1 stage 1)
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TF factor-bounds graph:
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this exponent TF target: 44
TF double-checked to: 67.9
ECM T-Level=29.87 ~= 83-bit
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Last modified: 2023-10-02T12:12:48+00:00