a(n) = 2*a(n-2)+4*a(n-4)+a(n-6), n>11.

Terms

a(0) =1a(1) =1a(2) =1a(3) =0a(4) =1a(5) =1a(6) =2a(7) =3a(8) =1a(9) =10a(10) =9a(11) =33a(12) =24a(13) =109a(14) =85a(15) =360a(16) =275a(17) =1189a(18) =914a(19) =3927a(20) =3013a(21) =12970a(22) =9957a(23) =42837a(24) =32880a(25) =141481a(26) =108601a(27) =467280a(28) =358679a(29) =1543321