a(n) = 17-n.

Terms

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