is 2 17761 - 1
has 5347 decimal digits
takes 0.000 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LC20DF650F99339E2double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual2671,672.986777.6119%100000000000801070519743994501,861,661.462340.4708%1,863,334.449086.6726%
Target2440.000165.9091%500100000.00001.5049%0.000166.4221%
Difference+23+1,672.9866+11.7028%+99999999500+80107051974389450+1,861,661.4623+38.9660%+1,863,334.4489+20.2505%

Known prime factors:
No known factors for M17761

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2001-04-29ANONYMOUSv4_computers10000010000000---0.000--1.793%
2001-07-29Alex Kruppav4_computers1000000100000000---0.003--4.471%
2001-08-18Alex Kruppav4_computers1000000100000000---0.003--4.471%
2002-04-28ANONYMOUSv4_computers163841638400---4.46828e-5--0.583%
2002-06-09ANONYMOUSv4_computers327683276800---8.93655e-5--0.950%
2002-07-14ANONYMOUSv4_computers655366553600---0.000--1.436%
2003-02-02ANONYMOUSv4_computers13107213107200---0.000--2.045%
2003-03-27ANONYMOUSv4_computers26214426214400---0.001--2.771%
2003-04-03ANONYMOUSv4_computers52428852428800---0.001--3.605%
2003-04-27ANONYMOUSv4_computers1048576104857600---0.003--4.538%
2003-05-19ANONYMOUSv4_computers2097152209715200---0.006--5.563%
2003-07-06ANONYMOUSv4_computers4194304419430400---0.011--6.674%
2003-09-29ANONYMOUSv4_computers8388608838860800---0.023--7.864%
2003-09-29ANONYMOUSv4_computers167772161677721600---0.046--9.122%
2012-12-12SergiosiManual testing500000000500000000---0.213--8.337%
2013-10-29David Campeaui5-2500k703330000703330000---0.300--8.869%
2013-11-11David Campeaui5-2500k937775000937775000---0.400--9.325%
2013-11-16David Campeaui5-2500k11722200001172220000---0.500--9.684%
2015-02-13JayderHPJared117222000035360118869---1.294--15.513%
2016-12-23James Hintz11_04_2016187348579811615611947612---3.455--17.611%
2019-05-20alexManual testing1000000000050000000000012---15.65--20.547%
2022-04-25-Anonymous-T581010000000000080107051974399450---1,861,661--40.471%


P+1 Factoring results:
dateuseridcompidb1b2startfactorSmoothdigitsbits*ghz-days
2021-05-12ATH5960X100000000024100000000027--6.651


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-10-15ANONYMOUSv4_computers252253--0.034--
2000-03-08ANONYMOUSv4_computers253254--0.068--
2000-09-23ANONYMOUSv4_computers21256--0.540--
2002-10-19ANONYMOUSv4_computers21257--1.081--
2016-02-23LaurVManual testing257258--1.081--
2010-06-22ANONYMOUSManual testing258259--2.162--
2010-06-22ANONYMOUSManual testing259260--4.324--
2012-12-25bcp19Manual testing260261--8.648--
2015-05-11snme2pm1G4261262--17.30--
2016-05-08Sid & AndyWoody262263--55.27--
2018-07-27snme2pm1g10263264--110.5--
2021-02-13Ruslan BorisovManual testing264265--210.4--
2022-02-23Ruslan BorisovManual testing265266--420.7--


ECM factoring results:
Total ECM effort:675.768 GHz-days
Estimated T-Level:45.715
DigitsB1CompleteFacMiss
20110002,185.0240.000%
2550000777.9040.000%
30250000193.7800.000%
35100000039.3570.000%
4030000006.9000.101%
45110000001.05234.908%
50440000000.14386.675%
551100000000.01898.249%
602600000000.00299.800%


ECM Summary

B1B2factorcurvesGHz-days
50000500000010.000
2500002500000010.002
10000001000000005553.406
30000003000000001011.860
11000000110000001034.715
1100000011000000007,439502.3
110000003513339103021.494
440000004400000000600162.0


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1997-01-01George WoltmanC20DF650F99339E25.22469e-6
2015-04-11MadPooManual testingC20DF650F99339E25.22469e-6


PRP results:
No PRP results for M17761


P-1 factor-bounds graph:
B1 = 100000000000, B2 = 80107051974399450 (P-1 stage 2)
B1 = 100000000000 (P-1 stage 1)
B1 = 10000000000, B2 = 500000000000 (P-1 stage 2)
B1 = 10000000000 (P-1 stage 1)
B1 = 1873485798, B2 = 116156119476 (P-1 stage 2)
B1 = 1172220000, B2 = 35360118869 (P-1 stage 2)
B1 = 1873485798 (P-1 stage 1)
B1 = 1172220000 (P-1 stage 1)
B1 = 937775000 (P-1 stage 1)
B1 = 703330000 (P-1 stage 1)
B1 = 500000000 (P-1 stage 1)
B1 = 16777216, B2 = 1677721600 (P-1 stage 2)
B1 = 8388608, B2 = 838860800 (P-1 stage 2)
B1 = 4194304, B2 = 419430400 (P-1 stage 2)
B1 = 16777216 (P-1 stage 1)
B1 = 2097152, B2 = 209715200 (P-1 stage 2)
B1 = 8388608 (P-1 stage 1)
B1 = 1048576, B2 = 104857600 (P-1 stage 2)
B1 = 1000000, B2 = 100000000 (P-1 stage 2)
B1 = 4194304 (P-1 stage 1)
B1 = 524288, B2 = 52428800 (P-1 stage 2)
B1 = 2097152 (P-1 stage 1)
B1 = 262144, B2 = 26214400 (P-1 stage 2)
B1 = 1048576 (P-1 stage 1)
B1 = 1000000 (P-1 stage 1)
B1 = 131072, B2 = 13107200 (P-1 stage 2)
B1 = 100000, B2 = 10000000 (P-1 stage 2)
B1 = 524288 (P-1 stage 1)
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 = 16384, B2 = 1638400 (P-1 stage 2)
B1 = 100000 (P-1 stage 1)
B1 = 65536 (P-1 stage 1)
B1 = 32768 (P-1 stage 1)
B1 = 16384 (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: 67.8
ECM T-Level=45.71 ~= 135-bit
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Last modified: 2023-04-26T21:34:10+00:00