a(n) = -a(n-1) - a(n-2) + a(n-3) - a(n-5).

Terms

a(0) =-1a(1) =0a(2) =2a(3) =-3a(4) =0a(5) =6a(6) =-9a(7) =1a(8) =17a(9) =-27a(10) =5a(11) =48a(12) =-81a(13) =21a(14) =135a(15) =-242a(16) =80a(17) =378a(18) =-721a(19) =288a(20) =1053a(21) =-2142a(22) =999a(23) =2917a(24) =-6346a(25) =3375a(26) =8030a(27) =-18750a(28) =11178a(29) =21948