Indices of primes in A027998.

Terms

a(0) =3a(1) =4a(2) =5a(3) =7a(4) =11a(5) =28a(6) =45a(7) =47a(8) =71a(9) =115a(10) =135a(11) =205a(12) =230a(13) =258a(14) =408a(15) =409a(16) =665a(17) =703a(18) =915a(19) =934a(20) =3912a(21) =5031a(22) =5746a(23) =6078a(24) =6391a(25) =7979a(26) =11267a(27) =11296a(28) =14666a(29) =17555