Numbers k such that k![4] - 4 is prime, where k![4] = A007662(k) = quadruple factorial.

Terms

a(0) =7a(1) =9a(2) =11a(3) =15a(4) =17a(5) =19a(6) =39a(7) =45a(8) =57a(9) =59a(10) =63a(11) =69a(12) =81a(13) =85a(14) =127a(15) =141a(16) =149a(17) =153a(18) =163a(19) =165a(20) =201a(21) =235a(22) =259a(23) =377a(24) =457a(25) =649a(26) =815a(27) =897a(28) =1057a(29) =1433