Number of nX3 0..1 arrays with every element equal to 2, 3, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

A300641

Number of nX3 0..1 arrays with every element equal to 2, 3, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Terms

    a(0) =0a(1) =2a(2) =2a(3) =10a(4) =30a(5) =104a(6) =340a(7) =1144a(8) =3795a(9) =12683a(10) =42227a(11) =140876a(12) =469517a(13) =1565586a(14) =5219130a(15) =17400850a(16) =58012053a(17) =193409644a(18) =644810491a(19) =2149754855a(20) =7167115016a(21) =23894640479a(22) =79662932803a(23) =265590322328a(24) =885458314722

External references