Woodall and Near Woodall primes

Woodall Primes

No. n # digits Normalized form Finder Date
1 2 1 23-1 Unknown
2 3 2 3·23-1 Unknown
3 6 3 3·27-1 Unknown
4 30 11 15·231-1 Hans Riesel 1968
5 75 25 75·275-1 Hans Riesel 1968
6 81 27 81·281-1 Hans Riesel 1968
7 115 37 115·2115-1
8 123 40 123·2123-1 Wilfrid Keller 1984
9 249 78 249·2249-1 Wilfrid Keller 1984
10 362 112 181·2363-1 Ingemar Jönsson 1972
11 384 119 3·2391-1 Hans Riesel 1969
12 462 142 231·2463-1 Wilfrid Keller 1984
13 512 157 2521-1 Raphael M. Robinson 1952-01-30
14 751 229 751·2751-1 Wilfrid Keller 1984
15 822 251 411·2823-1 Wilfrid Keller 1984
16 5312 1603 83·25318-1 Wilfrid Keller 1984-12
17 7755 2339 7755·27755-1 Wilfrid Keller 1984-12
18 9531 2874 9531·29531-1 Wilfrid Keller 1984-12
19 12379 3731 12379·212379-1 Wilfrid Keller 1984-12
20 15822 4768 7911·215823-1 Wilfrid Keller 1987-12
21 18885 5690 18885·218885-1 Wilfrid Keller 1987-12
22 22971 6920 22971·222971-1 Jeffrey Young 1997-05
23 23005 6930 23005·223005-1 Jeffrey Young 1997-05
24 98726 29725 49363·298727-1 Jeffrey Young 1997-05
25 143018 43058 71509·2143019-1 Ray Ballinger 1998-04-25
26 151023 45468 151023·2151023-1 Kevin O'Hare 1998-05-01
27 667071 200815 667071·2667071-1 Manfred Toplic 2000-09-25
28 1195203 359799 1195203·21195203-1 Mark Rodenkirch 2005-07-11
29 1268979 382007 1268979·21268979-1 Willem Siemelink 2007-01-25
30 1467763 441847 1467763·21467763-1 2007-06-07
31 2013992 606279 251749·22013995-1 Lasse Mejling Andersen 2007-08-09
32 2367906 712818 1183953·22367907-1 Stephen Kohlman 2007-09-03
33 3752948 1129757 938237·23752950-1 Matthew J Thompson 2007-12-26
34 17016602 5122515 8508301·217016603-1 Diego Bertolotti 2018-03-21

Near Woodall primes (form (n+1)·2n-1)

No. n # digits Normalized form Finder Date
1 1 1 22-1 Unknown
2 2 2 3·22-1 Unknown
3 3 2 25-1 Unknown
4 4 2 5·24-1 Unknown
5 5 3 3·26-1 Unknown
6 9 4 5·210-1 Unknown
7 14 6 15·214-1 Unknown
8 15 6 219-1 Pietro Cataldi 1588
9 16 7 17·216-1 Unknown
10 27 10 7·229-1 Unknown
11 45 16 23·246-1 Unknown
12 122 39 123·2122-1
13 125 40 63·2126-1
14 213 67 107·2214-1 Unknown
15 242 76 243·2242-1
16 256 80 257·2256-1
17 263 82 33·2266-1 Unknown
18 290 90 291·2290-1
19 855 261 107·2858-1 Unknown
20 1059 322 265·21061-1
21 2273 688 1137·22274-1
22 3945 1192 1973·23946-1
23 3999 1208 125·24004-1 Henri Lifchitz 1998-07-03
24 9512 2868 9513·29512-1 Henri Lifchitz 1998-07-03
25 14127 4257 883·214131-1 Henri Lifchitz 1998-07-03
26 16486 4967 16487·216486-1 Henri Lifchitz 1998-07-03
27 20056 6042 20057·220056-1 Henri Lifchitz 1998-07-03
28 28834 8685 28835·228834-1 Henri Lifchitz 1998-07-03
29 41493 12496 20747·241494-1 Henri Lifchitz 1998-07-03
30 159147 47914 39787·2159149-1 Ray Ballinger 2000-05-19
31 227139 68382 56785·2227141-1 Ray Ballinger 2000-07-28
32 587823 176959 36739·2587827-1 Steven Harvey 2009-09-11

Near Woodall primes (form (n-1)·2n-1)

No. n # digits Normalized form Finder Date
1 2 1 22-1 Unknown
2 4 2 3·24-1 Unknown
3 5 3 27-1 Unknown
4 11 5 5·212-1 Unknown
5 28 10 27·228-1 Unknown
6 35 13 17·236-1 Unknown
7 235 74 117·2236-1
8 325 101 81·2327-1
9 551 169 275·2552-1
10 688 210 687·2688-1
11 7037 2123 1759·27039-1
12 8896 2682 8895·28896-1
13 10020 3021 10019·210020-1 Mike Oakes
14 13597 4098 3399·213599-1 Mike Oakes
15 21347 6431 10673·221348-1 Henri Lifchitz 1998-07-03
16 118020 35533 118019·2118020-1 Steven Harvey 2002-06-27
17 446694 134474 446693·2446694-1 Steven Harvey 2008-09-25
18 659153 198431 41197·2659157-1 Steven Harvey 2010-02-01
19 665128 200230 665127·2665128-1 Steven Harvey 2010-02-09
20 790693 238029 197673·2790695-1 Steven Harvey 2010-11-17
21 1165667 350907 582833·21165668-1 Steven Harvey 2012-11-14
22 1172171 352865 586085·21172172-1 Steven Harvey 2012-10-03
23 1817933 547259 454483·21817935-1 Steven Harvey 2014-07-29