Indices of primes in the Padovan sequence A000931.

Terms

a(0) =8a(1) =9a(2) =10a(3) =12a(4) =13a(5) =19a(6) =24a(7) =35a(8) =42a(9) =89a(10) =133a(11) =474a(12) =671a(13) =1267a(14) =1578a(15) =2008a(16) =2215a(17) =2294a(18) =4168a(19) =5558a(20) =6572a(21) =8566a(22) =11235a(23) =18742a(24) =35839a(25) =44264a(26) =536490a(27) =727739