Number of n X 4 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 0 1 1 vertically.

Terms

a(0) =9a(1) =81a(2) =261a(3) =841a(4) =1943a(5) =4489a(6) =8643a(7) =16641a(8) =28509a(9) =48841a(10) =77129a(11) =121801a(12) =181131a(13) =269361a(14) =382503a(15) =543169a(16) =743633a(17) =1018081a(18) =1353069a(19) =1798281a(20) =2331999a(21) =3024121a(22) =3841451a(23) =4879681a(24) =6090213a(25) =7601049a(26) =9343473a(27) =11485321a(28) =13932179a(29) =16900321