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

Terms

a(0) =0a(1) =0a(2) =1a(3) =-1a(4) =-1a(5) =4a(6) =-3a(7) =-6a(8) =16a(9) =-7a(10) =-31a(11) =61a(12) =-6a(13) =-147a(14) =220a(15) =68a(16) =-655a(17) =739a(18) =639a(19) =-2772a(20) =2233a(21) =3950a(22) =-11188a(23) =5521a(24) =20805a(25) =-43035a(26) =6946a(27) =99929a(28) =-156856a(29) =-36056