Unique-period primes in base 3, sorted.
2, 5, 7, 11, 13, 41, 61, 73, 547, 757, 1093, 1181, 4561, 6481, 368089, 398581, 530713, 797161, 21523361, 42521761, 47763361, 2413941289, 23535794707, 282429005041, 374857981681, 926510094425921, 144542918285300809, 150094634909578633
1
T. D. Noe, Plot of 28 terms
Chris K. Caldwell, Unique prime
(Mma) nn = 1000; t3 = Table[c = Cyclotomic[n, 3]; c/GCD[n, c], {n, 2, nn}]; p3 = Select[t3, PrimePowerQ]; p3 = Table[FactorInteger[i][[1, 1]], {i, p3}]; Take[Sort[p3], 28]
Cf. A040017 (base-10 unique-period primes), A161509 (base 2), A064079.
Cf. S000019.
nonn,base
T. D. Noe, May 14 2014