Number of nX4 0..1 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..1 introduced in row major order.

A240515

Number of nX4 0..1 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..1 introduced in row major order.

Terms

    a(0) =5a(1) =10a(2) =28a(3) =99a(4) =326a(5) =1080a(6) =3765a(7) =13282a(8) =46928a(9) =166611a(10) =595402a(11) =2132856a(12) =7647821a(13) =27453594a(14) =98644580a(15) =354622219a(16) =1275200926a(17) =4586567656a(18) =16499401997a(19) =59359672578a(20) =213570572184a(21) =768440651027

External references