A234563 Number of (n+1) X (7+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).

49506, 64240, 83438, 128614, 195558, 358450, 635654, 1336954, 2694006, 6297370, 14043398, 35804074, 86353878, 236812570, 605170214, 1760412874, 4684644726, 14258344570, 38987644358, 122685304234, 341459442198, 1100585593690

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..72

Formula

Empirical: a(n) = 4*a(n-1) +30*a(n-2) -132*a(n-3) -331*a(n-4) +1720*a(n-5) +1530*a(n-6) -11280*a(n-7) -1324*a(n-8) +39136*a(n-9) -12360*a(n-10) -67968*a(n-11) +39456*a(n-12) +46080*a(n-13) -34560*a(n-14).

Example

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

Crossrefs

Column 7 of A234564.

Sequence in context: A235172 A251026 A210351 * A251881 A187856 A258320

Adjacent sequences: A234560 A234561 A234562 * A234564 A234565 A234566

Keyword

nonn

Author

R. H. Hardin, Dec 28 2013

Status

approved