15 480 281 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 =	1500000
B2 =	781676610

ECM

Digits	B1	Curves
25	50000	1 / 280

Estimated T-Level: 20.0 ⓘ

Status	Date	User	Residue	Shift
Verified	2002-11-02	Jim Gleason	110DDF1D87032037	9549302
Verified	2005-11-13	lingmob	110DDF1D87032037	3332528

History

Date	User	Type	Result
2024-08-22	Sid & Andy	NF-PM1	B1=1500000, B2=781676610
2023-06-10	Sid & Andy	NF	no factor from 2^72 to 2^73
2021-10-09	-Anonymous-	NF	no factor from 2^71 to 2^72
2021-09-16	SRBase	NF	no factor from 2^70 to 2^71
2021-06-15	lycorn	NF	no factor from 2^69 to 2^70
2018-02-16	ramgeis	NF	no factor from 2^68 to 2^69
2018-02-16	ramgeis	NF	no factor from 2^67 to 2^68
2017-01-09	Tha	NF-PM1	B1=300000, B2=6000000, E=12
2014-02-23	Nesowa	NF	no factor from 2^66 to 2^67
2013-09-15	David Campeau	NF	no factor from 2^65 to 2^66