Quantum factorials: (n-1)!! - (n-2)!! (mod n).

Terms

a(0) =1a(1) =1a(2) =0a(3) =1a(4) =5a(5) =1a(6) =0a(7) =1a(8) =2a(9) =3a(10) =0a(11) =1a(12) =0a(13) =1a(14) =0a(15) =9a(16) =2a(17) =15a(18) =0a(19) =1a(20) =2a(21) =9a(22) =0a(23) =1a(24) =0a(25) =7a(26) =0a(27) =15a(28) =2a(29) =1