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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).
1
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
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 22 2013
STATUS
approved