a(n) = 15-n.

Terms

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