A234241 Number of (n+1) X (1+1) 0..7 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 2 (constant-stress 1 X 1 tilings).

630, 6706, 72616, 790718, 8612920, 93934380, 1023822944, 11170450750, 121790634482, 1329240620840, 14497107132750, 158275185584352, 1726726741846356, 18858007382510560, 205796722132646470

Offset

1,1

Links

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

Formula

Empirical: a(n) = 7*a(n-1) +181*a(n-2) -1022*a(n-3) -7657*a(n-4) +21504*a(n-5) +54144*a(n-6) -96768*a(n-7) -80640*a(n-8).

Example

Some solutions for n=3:
  5 1   0 3   4 1   4 2   1 0   2 6   2 3   4 1   3 0   2 7
  7 5   2 3   2 1   3 3   7 4   3 5   7 6   7 6   5 4   2 5
  1 1   6 5   4 5   0 2   7 2   3 3   0 1   5 2   3 4   0 1
  5 7   4 5   1 4   5 5   5 2   3 1   1 4   1 0   0 3   5 4

Crossrefs

Column 1 of A234245.

Sequence in context: A110904 A171258 A234245 * A185849 A058832 A366489

Adjacent sequences: A234238 A234239 A234240 * A234242 A234243 A234244

Keyword

nonn

Author

R. H. Hardin, Dec 21 2013

Status

approved