Number of (n+2) X 3 binary arrays avoiding patterns 001 and 011 in rows and columns.

Terms

a(0) =108a(1) =324a(2) =720a(3) =1600a(4) =3000a(5) =5625a(6) =9450a(7) =15876a(8) =24696a(9) =38416a(10) =56448a(11) =82944a(12) =116640a(13) =164025a(14) =222750a(15) =302500a(16) =399300a(17) =527076a(18) =679536a(19) =876096a(20) =1107288a(21) =1399489a(22) =1739010a(23) =2160900a(24) =2646000a(25) =3240000a(26) =3916800a(27) =4734976a(28) =5659776a(29) =6765201