a(n) = n-15.

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