15 817 231 Exponent Status

Great Internet Mersenne Prime Search
GIMPS
Finding World Record Primes Since 1996

PrimeNet Exponent Status

M_n

Status

Details

Composite: proven not-prime with Lucas-Lehmer test

TF

No factors below 2⁷³

TF target 2⁶⁹

P-1

B1 =	5131000
B2 =	15857431590

ECM

Digits	B1	Curves
25	50000	1 / 280

Estimated T-Level: 20.0 ⓘ

Status	Date	User	Residue	Shift
Verified	2002-08-31	Mike Wetzel	CDD62EEACDC13251	9573221
Verified	2006-03-01	Ars Technica Team Prime Rib	CDD62EEACDC13251	13693480

History

Date	User	Type	Result
2024-09-17	Jason Lynch	NF-PM1	B1=5131000, B2=15857431590
2021-11-28	-Anonymous-	NF	no factor from 2^72 to 2^73
2021-09-22	-Anonymous-	NF	no factor from 2^71 to 2^72
2021-09-07	SRBase	NF	no factor from 2^70 to 2^71
2020-10-30	Tha	NF-PM1	B1=1500000, B2=30000000, E=12
2020-10-08	Yxinity	NF	no factor from 2^69 to 2^70
2018-02-06	ramgeis	NF	no factor from 2^68 to 2^69
2018-02-06	ramgeis	NF	no factor from 2^67 to 2^68
2016-03-16	Mark Rose	NF	no factor from 2^65 to 2^66
2014-07-20	Nesowa	NF	no factor from 2^66 to 2^67