208 367 Exponent Status

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GIMPS
Finding World Record Primes Since 1996

PrimeNet Exponent Status

M_n

Status

Details

Composite, with 3 known prime factors. Cofactor is composite.

Factored

Factor	Digits	Bits	Date
355611993314329042162913497	27	88.2	2019-11-29 07:09:14
1420858414984519803166335599	28	90.2	2011-06-12 05:34:30
386302117432043215935304285327	30	98.3	2020-05-05 07:30:10

ECM

Digits	B1	Curves
25	50000	280 / 280
30	250000	640 / 640
35	1000000	197 / 1566

Estimated T-Level: 30.6 ⓘ

TF below 2^97 is very unlikely to find new factors due to ECM effort.

Status	Date	User	Residue	Shift
Verified (Factored)		Allan Menezes	E2BB00CCD4C12D5E	0
Verified (Factored)		Peter Marksteiner	E2BB00CCD4C12D5E	0
Verified (Factored)		Eivind Triel	E2BB00CCD4C12D5E	183600
Verified (Factored)	2002-12-25	Brian J. Beesley	E2BB00CCD4C12D5E	174234

Status	Date	User	Residue	Number of known factors	Shift	Type	Base
Verified (Factored)	2017-09-22	Oliver Kruse	D5781E9C508B8CF6	1	0	1	3
Verified (Factored)	2017-10-12	kkmrkkblmbrbk	D5781E9C508B8CF6	1	149819	1	3
Verified (Factored)	2019-11-29	Niels_Mache_Nextcloud	8BB384377C90E9FA	2	115420	5	3
Verified (Factored)	2019-12-01	arnaud	8BB384377C90E9FA	2	62311	5	3
Verified (Factored)	2019-12-04	_p95holder_	8BB384377C90E9FA	2	151472	5	3
Verified	2020-05-05	M Miller	8BB384377C90E9FA	3	43955	5	3
Verified	2023-08-03	USAFSS	8BB384377C90E9FA	3	112609	5	3

History

Date	User	Type	Result
2023-08-03	curtisc	CERT	PRP Certification Proof certified good
2023-08-03	USAFSS	C-PRP	M208367/355611993314329042162913497/1420858414984519803166335599/386302117432043215935304285327 : 8BB384377C90E9FA PRP proof power = 5 PRP: Verified Proof certified good
2022-03-07	LordJulius	NF	no factor from 2^57 to 2^58
2022-03-07	LordJulius	NF	no factor from 2^54 to 2^55
2022-02-14	Oliver Kruse	NF-PM1	B1=30000000, B2=10070832992220
2021-05-11	Oliver Kruse	NF-PM1	B1=30000000, B2=3000000000
2020-05-05	M Miller	C-PRP	M208367/1420858414984519803166335599/355611993314329042162913497/386302117432043215935304285327 : 8BB384377C90E9FA PRP: Verified PRP without proof (small exponent)
2020-05-05	Greg Hogan	F-ECM	Factor: 386302117432043215935304285327 / (ECM curve 1, B1=250000, B2=25000000, Sigma=3499827619762676)
2019-12-04	_p95holder_	C-PRP	M208367/355611993314329042162913497/1420858414984519803166335599 : 8BB384377C90E9FA PRP: Verified PRP without proof (small exponent)
2019-12-01	arnaud	C-PRP	M208367/1420858414984519803166335599/355611993314329042162913497 : 8BB384377C90E9FA PRP: Verified PRP without proof (small exponent)
2019-11-29	Niels_Mache_Nextcloud	C-PRP	M208367/1420858414984519803166335599/355611993314329042162913497 : 8BB384377C90E9FA PRP: Verified PRP without proof (small exponent)
2019-11-29	_p95holder_	F-ECM	Factor: 355611993314329042162913497 / (ECM curve 1, B1=250000, B2=25000000)
2017-10-12	kkmrkkblmbrbk	C-PRP	M208367/1420858414984519803166335599 : D5781E9C508B8CF6 PRP: Verified PRP without proof (small exponent)
2017-09-22	Oliver Kruse	C-PRP	M208367/1420858414984519803166335599 : D5781E9C508B8CF6 PRP: Verified PRP without proof (not generated)
2017-09-22	Oliver Kruse	C-PRP	M208367/1420858414984519803166335599 : D5781E9C508B8CF6 PRP without proof (not generated)
2011-06-12	Sturle Sunde	F-ECM	Factor: 1420858414984519803166335599
2009-03-15	axn	NF-PM1	B1=5000000, B2=200000000, E=12
2009-01-25	Sturle Sunde	NF	no factor from 2^59 to 2^60
2009-01-01	Sturle Sunde	NF	no factor from 2^58 to 2^59