Numbers k such that 7^k - 2 is a prime.

Terms

a(0) =1a(1) =2a(2) =4a(3) =7a(4) =8a(5) =12a(6) =15a(7) =28a(8) =31a(9) =84a(10) =98a(11) =128a(12) =238a(13) =302a(14) =859a(15) =1508a(16) =1586a(17) =2091a(18) =2796a(19) =2888a(20) =3924a(21) =4815a(22) =5636a(23) =6596a(24) =7090a(25) =20176a(26) =22176a(27) =56386a(28) =84050a(29) =115515