Riesel primes of the form 241•2n-1

Current data

k , b : 241 , 2 Count : 28 Nash : 1600 Max n : 4,000,000 Date : 2021-03-21

11, 17, 19, 39, 69, 321, 653, 1109, 3819, 5729, 9659, 9911, 13217, 16707, 22307, 65107, 75419, 97587, 99667, 336197, 407709, 497679, 1208307, 1398869, 2135279, 2522801, 2857313, 3815727

History

• 2021-03-21: Checked n = 1 - 1000000, Gary Barnes, double check, results included
• 2019-03-04: Checked to n = 4000000, Thomas Ritschel, released
• 2019-01-08: Found n = 3815727, Thomas Ritschel
• 2018-10-10: Found n = 2857313, Thomas Ritschel
• 2018-09-12: Found n = 2522801, Thomas Ritschel
• 2018-08-13: Found n = 2135279, Thomas Ritschel
• 2018-06-18: Reserved by Thomas Ritschel, from n=2000000
• 2013-03-01: Checked to n = 2000000, Peter Benson, released
• 2013-02-24: Found n = 1398869, Peter Benson
• 2013-02-24: Reserved by Peter Benson from n=1300000
• 2012-05-14: Checked to n = 1300000, James P. Burt, released
• 2012-04-05: Found n = 1208307, James P. Burt
• 2011-12-31: Checked to n = 1100000, James P. Burt
• 2011-12-10: Reserved by James P. Burt from n=1000000
• 2009-07-30: Reserved by Borys Jaworski for sieving only n=1000000-5000000
• 2008-10-22: Checked to n = 1000000, NPLB Drive 4, released
• 2008-09-09: Checked n = 600000 - 607000, Michael Kwok
• 2008-09-09: Reserved by NPLB Drive 4
• 2008-08-30: Reserved by Michael Kwok
• 2006-12-16: Checked to n = 600000, RPS Drive 4, released
• 2006-09-18: Found n = 497679, Predrag Minovic, RPS Drive 4
• 2006-08-22: Found n = 407709, David Metcalfe, RPS Drive 4
• 2006-08-09: Found n = 336197, Thomas Ritschel, RPS Drive 4
• 2006-07-28: Reserved by RPS Drive 4, for n = 260000 - 600000
• 2006-03-05: none, Wilfrid Keller, released
• 2005-01-16: Reserved by Wilfrid Keller, for n = 230000 - 500000
• 2004-11-05: Checked n = 200000 - 230000, Steven Harvey, released
• 2004-08-16: Checked to n = 200000, Ingmar Goudt
• 2004-08-12: Checked to n = 168000, Ingmar Goudt
• 2004-08-10: Reserved by Ingmar Goudt