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

Terms

a(0) =9a(1) =81a(2) =289a(3) =729a(4) =1521a(5) =2809a(6) =4761a(7) =7569a(8) =11449a(9) =16641a(10) =23409a(11) =32041a(12) =42849a(13) =56169a(14) =72361a(15) =91809a(16) =114921a(17) =142129a(18) =173889a(19) =210681a(20) =253009a(21) =301401a(22) =356409a(23) =418609a(24) =488601a(25) =567009a(26) =654481a(27) =751689a(28) =859329a(29) =978121