a(n+3) = 2a(n+2) - 3a(n+1) + 2a(n); a(0) = 1, a(1) = -1, a(2) = -2.

Terms

a(0) =1a(1) =-1a(2) =-2a(3) =1a(4) =6a(5) =5a(6) =-6a(7) =-15a(8) =-2a(9) =29a(10) =34a(11) =-23a(12) =-90a(13) =-43a(14) =138a(15) =225a(16) =-50a(17) =-499a(18) =-398a(19) =601a(20) =1398a(21) =197a(22) =-2598a(23) =-2991a(24) =2206a(25) =8189a(26) =3778a(27) =-12599a(28) =-20154a(29) =5045