a(n) = -n.

Terms

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