42 407 327 Exponent Status

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

PrimeNet Exponent Status

M_n

Details

Composite: proven not-prime with Lucas-Lehmer test

No factors below 2⁷⁴

TF target 2⁷²

P-1

B1 =	505000
B2 =	12372500

Status	Date	User	Residue	Shift	Software
Bad	2008-10-05	Josef Spiess	1202AA2E7632854C	31912978	Windows,Prime95,v25 beta,(aka Wd1)
Verified	2015-11-17	endless_mike	D75663F9C98B4357	1352627	Windows 64-bit,Prime95,v28.7,build 1
Verified	2016-09-21	Mark Rose	D75663F9C98B4357	21106359	Linux 64-bit,Prime95,v28.9,build 2

History

Date	User	Type	Result
2022-04-10	TheJudger	NF	no factor TF: 73-74
2022-04-10	TheJudger	NF	no factor TF: 72-73
2016-09-21	Mark Rose	C-LL	D75663F9C98B4357
2015-11-17	endless_mike	C-LL	D75663F9C98B4357
2015-08-26	Greg	NF	no factor TF: 71-72
2015-03-20	Mark Rose	NF	no factor TF: 70-71
2015-02-08	chalsall	NF	no factor TF: 69-70
2014-01-05	LaurV	NF	no factor TF: 68-69
2008-10-04	Josef Spiess	C-LL	1202AA2E7632854C
2008-09-23	Josef Spiess	NF-PM1	B1=505000, B2=12372500
2007-06-15	subgenius	NF	no factor TF: 1-68