Odd powers of primes of the form q = x^2 + 1 (A002496).

Terms

a(0) =2a(1) =5a(2) =8a(3) =17a(4) =32a(5) =37a(6) =101a(7) =125a(8) =128a(9) =197a(10) =257a(11) =401a(12) =512a(13) =577a(14) =677a(15) =1297a(16) =1601a(17) =2048a(18) =2917a(19) =3125a(20) =3137a(21) =4357a(22) =4913a(23) =5477a(24) =7057a(25) =8101a(26) =8192a(27) =8837a(28) =12101a(29) =13457