Riesel primes of the form 381•2n-1

Reserved! This sequence is currently part of Multi Reservation 26: NPLB Drive 19.

Current data

k , b : 381 , 2 Type : 3 Count : 51 Nash : 2491 Max n : 3,100,000 Date : 2024-08-15 Reserved : No Prime Left BehindNo Prime Left Behind/Reserved

1, 2, 7, 9, 11, 17, 21, 27, 49, 61, 79, 119, 467, 1035, 2185, 2307, 2429, 2815, 3085, 3990, 4431, 4647, 4697, 6734, 11189, 12770, 13891, 19227, 20114, 29045, 31765, 49931, 59055, 67242, 67597, 81189, 115459, 115947, 206391, 230701, 288935, 303722, 398511, 469371, 618929, 1070022, 1302991, 1646029, 1974841, 2801281, 2820157

History

• 2023-02-20: Found n = 2820157, Max Dettweiler
• 2023-02-19: Found n = 2801281, Max Dettweiler
• 2022-06-03: Reserved by NPLB Drive 16, for 2000000<n<3000000
• 2014-12-28: Checked to n = 2000000, NPLB Maxi Drive 1, released
• 2014-12-15: Found n = 1974841, Lennart Vogel
• 2014-08-25: Found n = 1646029, Lennart Vogel
• 2014-08-20: Reserved by NPLB Maxi Drive 1, for 1610000<n<2000000
• 2013-04-28: Reserved by NPLB Maxi Drive 1, for 1300000<n<2000000
• 2013-02-18: Found n = 1070022, Ian M. Gunn
• 2013-01-14: Reserved by NPLB Maxi Drive 1, for 1000000<n<1300000
• 2009-10-18: Checked to n = 1000000, Ian M. Gunn, released
• 2009-10-14: Checked to n = 994000, Ian M. Gunn
• 2009-10-01: Checked to n = 974000, Ian M. Gunn
• 2009-08-30: Checked to n = 931000, Ian M. Gunn
• 2009-08-14: Checked to n = 910000, Ian M. Gunn
• 2009-07-20: Checked to n = 875000, Ian M. Gunn
• 2009-06-28: Checked to n = 840000, Ian M. Gunn
• 2009-06-09: Checked to n = 810000, Ian M. Gunn
• 2009-05-25: Checked to n = 787000, Ian M. Gunn
• 2009-05-12: Checked to n = 761000, Ian M. Gunn
• 2009-04-23: Checked to n = 723000, Ian M. Gunn
• 2009-04-11: Checked to n = 698000, Ian M. Gunn
• 2009-03-20: Checked to n = 647000, Ian M. Gunn
• 2009-03-11: Found n = 618929, Ian M. Gunn
• 2009-03-08: Checked to n = 609000, Ian M. Gunn
• 2009-03-01: Reserved by Ian M. Gunn, for 600000<n<1000000
• 2008-11-10: Checked to n = 600000, NPLB Drive 3, released
• 2008-05-02: Found n = 469371, Gary Barnes
• 2008-03-06: Found n = 303722, James P. Burt
• 2008-03-06: 288935 confirmed, James P. Burt
• 2008-03-01: Reserved by NPLB Drive 3, for 260000<n<600000
• 2005-07-14: Found n = 398511, Peter O'braian
• 2004-12-23: Found n = 288935, Peter O'braian
• 2004-10-31: Found n = 230701, Peter O'braian
• 2004-10-28: Found n = 206391, Peter O'braian
• 2003-02-05: Found n = 115947, Steven Harvey
• 2003-02-05: Found n = 115459, Steven Harvey
• 2001-03-09: Found n = 81189, Kimmo Herranen
• 2001-03-09: Found n = 67597, Kimmo Herranen
• 2001-03-09: Found n = 67242, Kimmo Herranen