A234263 Number of (n+1) X (5+1) 0..2 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 2 (constant-stress 1 X 1 tilings).

560, 754, 1100, 1816, 3188, 6076, 11876, 24340, 50180, 107044, 227780, 500356, 1090628, 2457796, 5468996, 12611140, 28568900, 67202884, 154536260, 369513796, 859910468, 2082568516, 4890632516, 11957948740, 28269265220, 69599027524

Offset

1,1

Links

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

Formula

Empirical: a(n) = 3*a(n-1) + 6*a(n-2) - 24*a(n-3) + 4*a(n-4) + 36*a(n-5) - 24*a(n-6).

Empirical g.f.: 2*x*(280 - 463*x - 2261*x^2 + 3716*x^3 + 3498*x^4 - 5580*x^5) / ((1 - x)*(1 - 2*x)*(1 - 2*x^2)*(1 - 6*x^2)). - Colin Barker, Oct 14 2018

Example

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

Crossrefs

Column 5 of A234266.

Sequence in context: A139197 A361030 A136346 * A100987 A100971 A253362

Adjacent sequences: A234260 A234261 A234262 * A234264 A234265 A234266

Keyword

nonn

Author

R. H. Hardin, Dec 22 2013

Status

approved