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

Terms

a(0) =-1a(1) =1a(2) =1a(3) =-5a(4) =9a(5) =-7a(6) =-9a(7) =41a(8) =-71a(9) =51a(10) =81a(11) =-335a(12) =559a(13) =-367a(14) =-719a(15) =2731a(16) =-4391a(17) =2601a(18) =6311a(19) =-22215a(20) =34409a(21) =-18077a(22) =-54879a(23) =180321a(24) =-268961a(25) =122401a(26) =473441a(27) =-1460645a(28) =2096809a(29) =-798887