Number of n X 3 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

Terms

a(0) =6a(1) =36a(2) =90a(3) =225a(4) =420a(5) =784a(6) =1260a(7) =2025a(8) =2970a(9) =4356a(10) =6006a(11) =8281a(12) =10920a(13) =14400a(14) =18360a(15) =23409a(16) =29070a(17) =36100a(18) =43890a(19) =53361a(20) =63756a(21) =76176a(22) =89700a(23) =105625a(24) =122850a(25) =142884a(26) =164430a(27) =189225a(28) =215760a(29) =246016