Number of (n+1)X(n+1) 0..2 arrays with the sums of 2X2 subblocks nondecreasing rightwards and downwards.

A204222

Number of (n+1)X(n+1) 0..2 arrays with the sums of 2X2 subblocks nondecreasing rightwards and downwards.

Terms

    a(0) =81a(1) =4539a(2) =752562a(3) =129062037a(4) =45791699846

External references