Number of nX6 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically.

Terms

a(0) =18a(1) =324a(2) =1350a(3) =3726a(4) =8280a(5) =16038a(6) =28224a(7) =46260a(8) =71766a(9) =106560a(10) =152658a(11) =212274a(12) =287820a(13) =381906a(14) =497340a(15) =637128a(16) =804474a(17) =1002780a(18) =1235646a(19) =1506870a(20) =1820448a(21) =2180574a(22) =2591640a(23) =3058236a(24) =3585150a(25) =4177368a(26) =4840074a(27) =5578650a(28) =6398676a(29) =7305930