Number of (n+1) X (1+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).

A234557

Number of (n+1) X (1+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) =70a(1) =220a(2) =618a(3) =1954a(4) =5506a(5) =17518a(6) =49506a(7) =158518a(8) =449170a(9) =1447510a(10) =4111458a(11) =13334374a(12) =37954546a(13) =123863638a(14) =353202306a(15) =1159606918a(16) =3311711890a(17) =10935135670a(18) =31268536098a(19) =103805608294a(20) =297121857586a(21) =991365572758

External references