A234891 Number of (n+1) X (1+1) 0..6 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 1, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).

160, 760, 3456, 16572, 76032, 365024, 1676576, 8050184, 36980544, 177566656, 815714624, 3916758000, 17993056384, 86395956032, 396891522944, 1905725225888, 8754648687872, 42036560942336, 193110382571776, 927244100524992

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 30*a(n-2) -194*a(n-4) +428*a(n-6) -288*a(n-8) +48*a(n-10).

Example

Some solutions for n=5:
  6 2   3 5   5 1   4 0   4 5   6 3   4 6   2 3   4 2   0 2
  4 1   2 3   3 0   6 3   0 2   5 1   0 1   0 2   3 0   3 6
  6 4   0 2   6 2   2 0   2 3   6 3   2 4   2 3   4 2   2 4
  5 2   4 5   3 0   6 3   0 2   3 1   3 6   0 2   2 1   5 6
  2 0   0 2   4 2   3 1   1 4   6 3   0 2   5 6   5 3   2 4
  4 3   3 6   1 0   5 2   3 5   2 0   4 5   2 4   2 1   3 6

Crossrefs

Column 1 of A234898.

Sequence in context: A234658 A234651 A234898 * A305272 A234450 A234444

Adjacent sequences: A234888 A234889 A234890 * A234892 A234893 A234894

Keyword

nonn

Author

R. H. Hardin, Jan 01 2014

Status

approved