Riesel primes of the form 31•2n-1

Reserved! This sequence is currently reserved by: Michael Curtis, Ryan Propper

Current data

k , b : 31 , 2 Count : 53 Nash : 2188 Max n : 3,350,000 Date : 2024-09-24 Reserved : Michael Curtis, Ryan PropperMichael Curtis/ReservedRyan Propper/Reserved

1, 5, 7, 11, 13, 23, 33, 35, 37, 47, 115, 205, 235, 271, 409, 739, 837, 887, 2189, 3465, 4653, 5073, 8011, 8061, 21957, 24589, 25657, 44653, 50321, 57647, 62083, 78179, 80021, 81655, 111667, 150265, 177089, 196433, 274115, 306751, 311389, 315523, 406105, 421129, 666285, 773227, 1142093, 1611311, 1755317, 2585311, 3259185, 3326149, 9088085

Remarks :

See also Williams 31•32n-1

History

• 2024-09-24: Checked n = 3259185 - 3350000, Michael Curtis
• 2024-09-24: Found n = 3326149, Michael Curtis
• 2024-08-27: Found n = 9088085, Ryan Propper
• 2024-08-16: Reserved by Ryan Propper, for n = 6000000 - 12000000
• 2024-05-22: Checked n = 3000000 - 3259185, Michael Curtis
• 2024-05-20: Found n = 3259185, Michael Curtis
• 2023-07-17: Checked n = 2282000 - 3000000, Michael Curtis
• 2022-12-03: Found n = 2585311, Michael Curtis
• 2021-03-21: Checked n = 1 - 1000000, Gary Barnes, double check, results included
• 2021-02-13: Reserved by Michael Curtis
• 2016-01-27: Checked to n = 2282000, Steven Tjung
• 2014-01-13: Checked to n = 2100000, Steven Tjung
• 2014-09-13: Checked to n = 2066000, Steven Tjung
• 2013-08-22: none, Steven Tjung
• 2012-08-19: Checked to n = 2020000, Steven Tjung
• 2011-01-28: Found n = 1755317, Steven Tjung
• 2010-02-24: Found n = 1611311, Steven Tjung
• 2009-12-05: Checked to n = 1600000, Steven Tjung
• 2009-10-06: Checked to n = 1570000, Steven Tjung
• 2009-07-26: Checked n = 1650000 - 1652063?, (unknown), See range done at RPS other completed ranges.
• 2009-05-15: Checked to n = 1510000, Steven Tjung
• 2009-04-06: Checked to n = 1370000, Steven Tjung
• 2009-02-12: Checked to n = 1350000, Steven Tjung
• 2009-01-09: Checked n = 950000 - 1015948, 1140029 - 1162645, 1430011 - 1445009, 1652063 - 1722449, 1967593 - 2002883, Peter Benson
• 2008-12-09: Found n = 421129, Raffaele De Troia, missing prime found
• 2008-12-02: Found n = 406105, Raffaele De Troia, missing prime found
• 2008-11-21: Checked to n = 1300000, Steven Tjung
• 2008-04-02: Found n = 1142093, Peter Benson
• 2008-01-31: Checked to n = 735000, Steven Tjung
• 2008-01-02: Checked to n = 707000, Steven Tjung
• 2007-12-30: Found n = 666285, Steven Tjung
• 2007-12-08: Checked to n = 685000, Steven Tjung
• 2007-12-07: Found n = 773227, Steven Tjung
• 2007-11-01: Checked to n = 645000, Steven Tjung
• 2007-09-06: Checked to n = 570000, Steven Tjung
• 2007-07-13: Checked to n = 567000, Steven Tjung
• 2007-06-25: Checked to n = 558000, Steven Tjung
• 2007-04-22: Checked to n = 527000, Steven Tjung
• 2007-03-10: Checked to n = 525000, Steven Tjung
• 2007-01-12: Checked to n = 507000, Steven Tjung
• 2006-11-03: Reserved by Steven Tjung
• 2004-08-18: Checked to n = 500000, Steven Harvey, released
• 2004-08-06: Checked to n = 494600, Steven Harvey
• 2004-08-03: Checked to n = 493000, Steven Harvey
• 2004-08-01: Checked to n = 492500, Steven Harvey
• 2004-07-26: Checked to n = 492000, Steven Harvey
• 2004-06-24: Checked to n = 426000, Steven Harvey
• 2004-05-19: Checked to n = 395119, Steven Harvey
• 2004-04-28: Found n = 315523, Steven Harvey
• 2004-04-27: Checked to n = 313000, Steven Harvey
• 2004-04-27: Found n = 311389, Steven Harvey
• 2004-04-26: Checked n = 1 - 143000,150000 - 307553, Steven Harvey
• 2004-04-26: Found n = 306751, Steven Harvey
• 2004-04-21: Checked n = 110000 - 120000,150000 - 294739, Steven Harvey
• 2004-04-19: Found n = 274115, Steven Harvey
• 2004-04-05: Found n = 196433, Steven Harvey
• 2004-04-04: Found n = 177089, Steven Harvey
• 2003-03-20: Found n = 111667, Steven Harvey
• 2000-06-03: Found n = 62083, Phil Carmody
• 2000-05-31: Found n = 57647, Phil Carmody
• 2000-05-22: Found n = 44653, Phil Carmody
• 1998-08-13: Found n = 25657, Wilfrid Keller
• 1998-08-13: Found n = 24589, Wilfrid Keller
• 1998-08-09: Found n = 21957, Wilfrid Keller