Number of 2 X n 0..2 arrays x(i,j) with each element horizontally or antidiagonally next to at least one element with value 2-x(i,j).

A230185

Number of 2 X n 0..2 arrays x(i,j) with each element horizontally or antidiagonally next to at least one element with value 2-x(i,j).

Terms

    a(0) =0a(1) =9a(2) =27a(3) =159a(4) =825a(5) =4395a(6) =23307a(7) =123729a(8) =656715a(9) =3485775a(10) =18502017a(11) =98206299a(12) =521266155a(13) =2766812505a(14) =14685878427a(15) =77950719519a(16) =413752211145

External references