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Status of the smallest base values yielding Generalized Fermat primes

In 1986, Harvey Dubner published a table of the smallest integers b such that GF(n, b) is prime (J. Recr. Math., 18, 1986). The following table reports Harvey Dubner's results and some more recent results.

n N The first ten bases b for which GF(n, b) is prime
1 2 2, [4], 6, 10, 14, [16], 20, 24, 26, [36], 40, 54, 56, ...
2 4 2, [4], 6, [16], 20, 24, 28, 34, 46, 48, 54, 56, ...
3 8 2, [4], 118, 132, 140, 152, 208, 240, 242, 288, 290, ...
4 16 2, 44, 74, 76, 94, 156, 158, 176, 188, 198, ...
5 32 30, 54, 96, 112, 114, 132, 156, 332, 342, 360, ...
6 64 102, 162, 274, 300, 412, 562, 592, 728, 1084, 1094, ...
7 128 120, 190, 234, 506, 532, 548, 960, 1738, 1786, 2884, ...
8 256 278, 614, 892, 898, 1348, 1494, 1574, 1938, [2116], 2122, 2278, ...
9 512 46, 1036, 1318, 1342, 2472, 2926, 3154, 3878, 4386, 4464, ...
10 1024 824, 1476, 1632, 2462, 2484, 2520, 3064, 3402, 3820, 4026, ...
11 2048 150, 2558, 4650, 4772, 11272, 13236, 15048, 23302, 26946, 29504, ...
12 4096 1534, 7316, 17582, 18224, 28234, 34954, 41336, 48824, 51558, 51914, ...
13 8192 30406, 71852, 85654, 111850, 126308, 134492, 144642, 147942, 150152, 165894, ...
14 16384 67234, 101830, 114024, 133858, 162192, 165306, 210714, 216968, 229310, 232798, ...
15 32768 70906, 167176, 204462, 249830, 321164, 330716, 332554, 429370, 499310, 524552, ... 

The test of all the GF(n, b) up to some large limits is completed:

n = 1, N = 2, B < 109, 34900212 Generalized Fermat primes
n = 2, N = 4, B < 108, 3857543 Generalized Fermat primes
n = 3, N = 8, B < 107, 174368 Generalized Fermat primes
n = 4, N = 16, B < 107, 152447 Generalized Fermat primes
n = 5, N = 32, B < 107, 74951 Generalized Fermat primes
n = 6, N = 64, B < 107, 41059 Generalized Fermat primes
n = 7, N = 128, B < 9 106, 14586 Generalized Fermat primes
n = 8, N = 256, B < 7 106, 13890 Generalized Fermat primes
n = 9, N = 512, B < 6 106, 6138 Generalized Fermat primes
n = 10, N = 1024, B < 5 106, 2614 Generalized Fermat primes
n = 11, N = 2048, B < 4 106, 1000 Generalized Fermat primes
n = 12, N = 4096, B < 3 106, 435 Generalized Fermat primes
n = 13, N = 8192, B < 2.6 106, >= 90 Generalized Fermat primes*
n = 14, N = 16384, B < 2.7 106, >= 89 Generalized Fermat primes*
n = 15, N = 32768, B < 2.2 106, >= 35 Generalized Fermat primes*
n = 16, N = 65536, B < 1.1 105, >= 2 Generalized Fermat prime*

*The range was tested only once. The number of primes will be considered as correct when the range is double-checked. However, the tests of significance indicate that the result is probably correct.