Number of n X 3 0..1 arrays with every element unequal to 0, 1 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

A299590

Number of n X 3 0..1 arrays with every element unequal to 0, 1 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Terms

    a(0) =3a(1) =3a(2) =5a(3) =11a(4) =19a(5) =35a(6) =65a(7) =120a(8) =220a(9) =404a(10) =744a(11) =1369a(12) =2517a(13) =4629a(14) =8515a(15) =15662a(16) =28806a(17) =52982a(18) =97450a(19) =179239a(20) =329671a(21) =606359a(22) =1115269a(23) =2051300a(24) =3772928a(25) =6939496a(26) =12763724a(27) =23476149a(28) =43179369a(29) =79419241

External references