Numbers k such that 9^k - 3^k - 1 is prime.

Terms

a(0) =1a(1) =2a(2) =3a(3) =6a(4) =7a(5) =20a(6) =35a(7) =36a(8) =140a(9) =523a(10) =1170a(11) =1731a(12) =1842a(13) =3727a(14) =3886a(15) =9270a(16) =11071a(17) =13823a(18) =14451a(19) =27086a(20) =27606a(21) =31876a(22) =78008