42 205 183 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 2⁷³

TF target 2⁷²

P-1

B1 =	510000
B2 =	14152500

Status	Date	User	Residue	Shift	Software
Verified	2010-05-12	Kyle Z Schmidt	99900D19C2A66215	21649523	Windows,Prime95,v24 final,(aka Wc1)
Verified	2016-02-15	thatcactusgirl	99900D19C2A66215	8244117	Windows 64-bit,Prime95,v28.7,build 1

History

Date	User	Type	Result
2022-04-27	RichD0	NF	no factor TF: 72-73
2016-02-15	thatcactusgirl	C-LL	99900D19C2A66215
2015-08-25	AirSquirrels	NF	no factor TF: 71-72
2015-03-04	Mark Rose	NF	no factor TF: 70-71
2015-01-21	1997rj7	NF	no factor TF: 69-70
2013-12-20	Torben K.	NF	no factor TF: 68-69
2010-05-12	Kyle Z Schmidt	C-LL	99900D19C2A66215
2008-06-22	-anonymous-	NF-PM1	B1=510000, B2=14152500
2007-05-28	sasaki3	NF	no factor TF: 1-68