Marin Mersenne 2^P-1
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MnStatusDetails
4261987Composite, with 1 known prime factor. Cofactor is composite.
Factored
FactorDigitsBitsDate
1480873095823728171831592477.02022-05-24 19:27:39
ECM
DigitsB1Curves
255000012 / 280
Estimated T-Level: 20.2 ⓘ
TF below 2^62 is very unlikely to find new factors due to ECM effort.
LL
StatusDateUserResidueShift
Verified (Factored)1998-06-07Dan Tandberg5D1E0AD1F48557AD0
Verified (Factored)2000-03-01Stephen Jazdzewski5D1E0AD1F48557AD666115
PRP Cofactor
StatusDateUserResidueNumber of
known factors		ShiftTypeBase
Verified2022-05-31LaurV38BDE4F9D1E2453E197158253
P-1 factors
DateFactorB1B2
2022-05-2414808730958237281718315962000006200000
History
DateUserTypeResult
2022-09-08USAFSSNF-PM1
B1=280000, B2=139094670
2022-05-31Ge yongCERT
PRP Certification
Proof certified good
2022-05-31LaurVC-PRP
M4261987/148087309582372817183159 : 38BDE4F9D1E2453E
PRP proof power = 7
PRP: Verified
Proof certified good
2022-05-24DRobinsonPEF-PM1
Factor: 148087309582372817183159 / (P-1, B1=6200000)
2021-01-23-Anonymous-NF
no factor from 2^70 to 2^71
2021-01-22-Anonymous-NF
no factor from 2^69 to 2^70
2021-01-22-Anonymous-NF
no factor from 2^68 to 2^69
2018-11-13chuenkitNF
no factor from 2^67 to 2^68
2018-04-24chuenkitNF
no factor from 2^66 to 2^67
2016-02-23Mark RoseNF
no factor from 2^62 to 2^63
2015-06-11snme2pm1NF
no factor from 2^65 to 2^66
2013-12-30lycornNF
no factor from 2^64 to 2^65
2013-12-28JayderNF
no factor from 2^63 to 2^64
2013-10-16Squeeky_SquirrelNF-PM1
B1=145000, B2=3588750, E=6
2012-01-31GrunwalderGIMPNF
no factor from 2^1 to 2^63
2011-08-20Squeeky_SquirrelNF-PM1
B1=50000, B2=762500, E=6
2011-01-08markrNF
no factor from 2^61 to 2^62
2009-08-04Carsten KossendeyNF-PM1
B1=25000, B2=337500