Numbers k such that 3^k + 20 is prime.

Terms

a(0) =1a(1) =2a(2) =3a(3) =4a(4) =5a(5) =7a(6) =8a(7) =10a(8) =11a(9) =14a(10) =44a(11) =55a(12) =68a(13) =71a(14) =80a(15) =123a(16) =158a(17) =213a(18) =220a(19) =272a(20) =668a(21) =725a(22) =885a(23) =1132a(24) =1677a(25) =2056a(26) =2618a(27) =3130a(28) =3986a(29) =6027