a(n)=4a(n-1)-7a(n-2)+6a(n-3)-3a(n-4), n>4.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =1a(5) =4a(6) =9a(7) =14a(8) =14a(9) =0a(10) =-41a(11) =-122a(12) =-243a(13) =-364a(14) =-364a(15) =0a(16) =1093a(17) =3280a(18) =6561a(19) =9842a(20) =9842a(21) =0a(22) =-29525a(23) =-88574a(24) =-177147a(25) =-265720a(26) =-265720a(27) =0a(28) =797161a(29) =2391484