a(n) = n-11.

Terms

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