Number of (n+1) X (2+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant-stress 1 X 1 tilings).

A234558

Number of (n+1) X (2+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant-stress 1 X 1 tilings).

Terms

    a(0) =220a(1) =546a(2) =1240a(3) =3384a(4) =8416a(5) =24420a(6) =64240a(7) =194124a(8) =527920a(9) =1640076a(10) =4548400a(11) =14411004a(12) =40441936a(13) =130023180a(14) =367611280a(15) =1195404444a(16) =3396165040a(17) =11145399276a(18) =31767426160a(19) =105049443324a(20) =300084387856a(21) =998758590540

External references