Number of (n+1)X8 0..3 arrays with every 2X2 subblock having nonzero determinant and commuting with every horizontal or vertical neighbor.

A206342

Number of (n+1)X8 0..3 arrays with every 2X2 subblock having nonzero determinant and commuting with every horizontal or vertical neighbor.

Terms

    a(0) =4111a(1) =2042a(2) =12005a(3) =6078a(4) =36015a(5) =18258a(6) =108141a(7) =54762a(8) =324087a(9) =163950a(10) =971925a(11) =491514a(12) =2915439a(13) =1474206a(14) =8746143a(15) =4422606a(16) =26238417a(17) =13267806a(18) =78715239a(19) =39803406a(20) =236145705a(21) =119410206a(22) =708437103a(23) =358230606a(24) =2125311297a(25) =1074691806

External references