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

Terms

a(0) =-1a(1) =0a(2) =-3a(3) =2a(4) =-8a(5) =9a(6) =-23a(7) =33a(8) =-70a(9) =113a(10) =-220a(11) =376a(12) =-703a(13) =1235a(14) =-2265a(15) =4032a(16) =-7327a(17) =13126a(18) =-23748a(19) =42673a(20) =-77043a(21) =138641a(22) =-250054a(23) =450293a(24) =-811760a(25) =1462292a(26) =-2635519a(27) =4748343a(28) =-8557089a(29) =15418256