1 940 479 Exponent Status

PrimeNet Exponent Status

M_n

Status

Details

Composite: proven not-prime with both PRP and Lucas-Lehmer tests

No factors below 2⁶⁸

TF target 2⁶²

TF below 2^81 is very unlikely to find new factors due to ECM effort.

P-1

B1 =	50000000
B2 =	256102416570

ECM

Digits	B1	Curves
25	50000	280 / 280
30	250000	131 / 640

Estimated T-Level: 26.0 ⓘ

Status	Date	User	Residue	Shift
Verified	1998-02-19	Wayne Yeung	D1099B1D7D319908	0
Verified	1999-01-10	Dale Sullins	D1099B1D7D319908	1931173
Verified	2015-07-12	MadPoo	D1099B1D7D319908	1156979

Status	Date	User	Residue	Shift	Type	Base
Verified	2025-09-02	Kriesel	DCBCA55D78771216	0	1	3

History

Date	User	Type	Result
2025-09-03	EthanD	CERT	PRP Certification CERT proof power = 6 Proof certified good
2025-09-02	Kriesel	C-PRP	DCBCA55D78771216 PRP proof power = 6 PRP: Verified Proof certified good
2023-04-25	RichD0	NF-PM1	B1=50000000, B2=256102416570
2022-08-16	masser	NF-PP1	Start=2/7, B1=1500000, B2=54000000
2022-08-06	Wentao Huang	NF-PM1	B1=2330000, B2=10302160050
2019-05-11	chuenkit	NF	no factor from 2^67 to 2^68
2018-05-03	Joss	NF-PM1	B1=1940479, B2=194047900, E=12
2018-03-02	Joss	NF-PM1	B1=1940479, B2=120000000, E=12
2018-02-11	Joss	NF-PM1	B1=1940479, B2=60000000, E=12
2018-01-28	Joss	NF-PM1	B1=1940479, B2=30000000, E=12
2017-11-24	TJAOI	NF	no factor from 2^66 to 2^67
2016-02-23	Mark Rose	NF	no factor from 2^62 to 2^63
2016-02-23	Mark Rose	NF	no factor from 2^61 to 2^62
2016-02-23	Mark Rose	NF	no factor from 2^58 to 2^60
2015-09-05	ramgeis	NF	no factor from 2^65 to 2^66
2015-07-12	MadPoo	C-LL	D1099B1D7D319908
2015-05-06	lycorn	NF	no factor from 2^64 to 2^65
2015-05-06	lycorn	NF	no factor from 2^63 to 2^64
2011-10-28	kurly	NF-PM1	B1=1000000, B2=30000000, E=12
2011-08-27	GrunwalderGIMP	NF	no factor from 2^1 to 2^63
2010-01-28	S485122	NF	no factor from 2^60 to 2^61

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