Riesel primes of the form 21•2n-1

Current data

k , b : 21 , 2 Type : 3 Count : 45 Nash : 2103 Max n : 3,500,000 Date : 2024-05-07

1, 2, 3, 7, 10, 13, 18, 27, 37, 51, 74, 157, 271, 458, 530, 891, 1723, 1793, 1849, 1986, 2191, 2869, 4993, 7777, 11730, 15313, 29171, 35899, 36227, 71570, 199219, 233914, 297499, 332523, 348547, 538657, 986130, 999599, 1170083, 1182083, 1452771, 1872923, 2160479, 2959789, 6468257

Remarks :

The sequence A002238 in OEIS

History

• 2024-05-07: Reservation dropped, William Byerly
• 2021-10-22: Checked n = 6000000 - 7000000, Ryan Propper
• 2021-10-14: Found n = 6468257, Ryan Propper
• 2021-09-27: Reserved by William Byerly
• 2021-07-24: Checked n = 1000000 - 3500000, Gary Barnes, released, double-check for n = 1000000 - 2890000, results included
• 2021-06-27: Found n = 2959789, Gary Barnes
• 2021-05-10: Reserved by Gary Barnes for n = 1000000 - 3500000
• 2021-03-21: Checked n = 1 - 1000000, Gary Barnes, double-check, results included
• 2015-03-01: Checked n = 2865000 - 2890000, Predrag Minovic
• 2014-10-05: Checked n = 2500000 - 2865000, Predrag Minovic
• 2013-09-08: Checked n = 2450000 - 2500000, Predrag Minovic
• 2013-07-09: Checked n = 2220000 - 2450000, Predrag Minovic
• 2013-01-04: Checked n = 2040000 - 2220000, Predrag Minovic
• 2012-11-06: Found n = 2160479, Predrag Minovic
• 2012-07-02: Checked n = 1945000 - 1967593, 2035106 - 2040000, Predrag Minovic
• 2012-05-04: Checked n = 1910000 - 1945000, Predrag Minovic
• 2012-03-04: Checked n = 1860000 - 1910000, Predrag Minovic
• 2012-01-11: Found n = 1872923, Predrag Minovic
• 2011-12-31: Checked n = 1750000 - 1860000, Predrag Minovic
• 2011-06-04: Checked n = 1590000 - 1647000, Predrag Minovic, n = 1647000 - 1750000 done previously by Peter Benson & (unknown)
• 2011-04-12: Checked n = 1575000 - 1590000, Predrag Minovic
• 2011-03-05: Checked n = 1525000 - 1575000, Predrag Minovic
• 2011-01-13: Checked n = 1500000 - 1525000, Predrag Minovic
• 2010-10-31: Checked n = 1470000 - 1500000, Predrag Minovic
• 2010-09-05: Checked n = 1400000 - 1430007, 1454797 - 1455138, 1468063 - 1470000, Predrag Minovic
• 2010-07-18: Checked n = 1320000 - 1400000, Predrag Minovic
• 2010-05-04: Checked n = 1290000 - 1320000, Predrag Minovic
• 2010-04-11: Checked n = 1230000 - 1290000, Predrag Minovic
• 2010-02-11: Checked n = 1200000 - 1230000, Predrag Minovic
• 2009-08-29: Checked n = 1185000 - 1200000, Predrag Minovic
• 2009-08-09: Checked n = 1090000 - 1140000, 1181000 - 1185000, Predrag Minovic
• 2009-08-02: Found n = 1182083, Predrag Minovic
• 2009-07-26: Checked n = 1647000 - 1652069, 2320000 - 2322000, (unknown), See ranges done at RPS other completed ranges.
• 2009-05-31: Checked n = 1075000 - 1090000, Predrag Minovic
• 2009-02-13: Checked n = 1000000 - 1075000, Predrag Minovic
• 2009-01-09: Checked n = 950000 - 1032065, 1140002 - 1181063, 1430007 - 1454797, 1455138 - 1468063, 1652069 - 1750090, 1967593 - 2035106, Peter Benson
• 2008-04-06: Found n = 1452771, Peter Benson
• 2008-03-16: Found n = 1170083, Peter Benson
• 2006-10-13: Checked n = 950000 - 1000000, Predrag Minovic
• 2005-07-14: Found n = 986130, Predrag Minovic
• 2005-03-22: Checked n = 880000 - 950000, Predrag Minovic
• 2005-03-21: Found n = 999599, Predrag Minovic
• 2004-12-30: Checked n = 820000 - 880000, Predrag Minovic
• 2004-11-04: Checked n = 760000 - 820000, Predrag Minovic
• 2004-10-11: Checked n = 553000 - 760000, Predrag Minovic
• 2004-08-15: Checked n = 515000 - 553000, Predrag Minovic
• 2004-08-11: Checked n = 500000 - 515000, Predrag Minovic
• 2004-08-11: Found n = 538657, Predrag Minovic
• 2004-08-03: Reserved by Predrag Minovic from n = 500000
• 2004-06-25: Checked n = 495000 - 500000, Steven Harvey, released
• 2004-06-24: Checked n = 450491 - 495000, Steven Harvey
• 2004-05-23: Reserved by Justin Van Klein???
• 2004-05-19: Checked n = 260274 - 450491, Steven Harvey
• 2004-05-07: Found n = 348547, Steven Harvey
• 2004-05-05: Found n = 332523, Steven Harvey
• 2004-04-30: Found n = 297499, Steven Harvey
• 2004-04-26: Checked n = 1 - 260274, Steven Harvey
• 2004-04-21: Checked n = 1 - 75523, 110000 - 120000, 151000 - 254394, 399589 - 400000, Steven Harvey
• 2004-04-17: Found n = 233914, Steven Harvey
• 2004-04-03: Found n = 199219, Steven Harvey
• 1999-07-04: Found n = 71570, Michael J. Graef
• 1999-05-29: Found n = 36227, Michael J. Graef
• 1999-05-29: Found n = 35899, Michael J. Graef
• 1998-08-11: Found n = 29171, Wilfrid Keller
• 1994: Found n = 7777, Harvey Dubner