42 680 887 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 2⁷⁶

TF target 2⁷²

P-1

B1 =	520000
B2 =	15210000

Status	Date	User	Residue	Shift	Software
Verified	2011-07-18	WR	6595A9B7D0D26C8D	4501614	Linux 64-bit,Prime95,v26.5,build 5
Bad	2018-01-28	ktony	66F52E354B6D9255	17635863	Windows 64-bit,Prime95,v29.4,build 5
Bad	2018-01-28	ktony	32B4A4EF4F7BEA60	17635863	Windows 64-bit,Prime95,v29.4,build 5
Verified	2018-01-30	MadPoo 🙂	6595A9B7D0D26C8D	12058888	Windows 64-bit,Prime95,v29.4,(aka Wg4)

History

Date	User	Type	Result
2021-06-27	-anonymous-	NF	no factor TF: 75-76
2021-05-21	Yves de Wandelaar	NF	no factor TF: 74-75
2020-01-11	-anonymous-	NF	no factor TF: 73-74
2019-10-04	-anonymous-	NF	no factor TF: 72-73
2018-01-30	MadPoo 🙂	C-LL	6595A9B7D0D26C8D
2018-01-28	ktony	C-LL	32B4A4EF4F7BEA60
2018-01-28	ktony	C-LL	66F52E354B6D9255
2015-09-01	-anonymous-	NF	no factor TF: 71-72
2015-03-28	Mark Rose	NF	no factor TF: 70-71
2014-06-24	Grant McCracken	NF	no factor TF: 69-70
2014-01-07	Torben K.	NF	no factor TF: 68-69
2011-07-18	WR	C-LL	6595A9B7D0D26C8D
2008-06-22	-anonymous-	NF-PM1	B1=520000, B2=15210000, E=6
2007-07-24	RMAC9.5	NF	no factor TF: 1-68
2007-07-04	ComputerraRU	NF	no factor TF: 63-64
2007-07-04	ComputerraRU	NF	no factor TF: 62-63