Period 2: repeat (9,10).

Terms

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