Unique-period primes in base 7 in the order they are found.
2, 19, 5, 2801, 43, 1201, 16148168401, 117307, 11898664849, 13564461457, 6568801, 29078814248401, 13841169553, 3421093417510114543, 33232924804801, 79787519018560501, 1628413557556843, 5457586804596062091175455674392801, 402488219476647465854701
1
T. D. Noe, Plot of 48 terms
T. D. Noe, Table of 48 terms
Chris K. Caldwell, Unique prime
(Mma) nn = 100; t7 = Table[c = Cyclotomic[n, 7]; c/GCD[n, c], {n, 2, nn}]; p7 = Select[t7, PrimePowerQ]; Table[FactorInteger[i][[1, 1]], {i, p7}]
Cf. A040017 (base-10 unique-period primes), A161509 (base 2), A064083.
nonn,base
T. D. Noe, May 14 2014