Number of n X 3 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1 or 5 neighboring 1s.

A297590

Number of n X 3 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1 or 5 neighboring 1s.

Terms

    a(0) =1a(1) =3a(2) =9a(3) =25a(4) =69a(5) =205a(6) =597a(7) =1701a(8) =4949a(9) =14389a(10) =41493a(11) =120149a(12) =348437a(13) =1008021a(14) =2917653a(15) =8451605a(16) =24467733a(17) =70830869a(18) =205101333a(19) =593841429a(20) =1719269653a(21) =4977934613a(22) =14412904725a(23) =41729378581a(24) =120820070677a(25) =349814724885

External references