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A234683 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 5 (constant stress 1 X 1 tilings). 1
232, 1148, 5472, 27344, 131200, 661952, 3196416, 16276736, 79071232, 406166528, 1984192512, 10274852864, 50451742720, 263191642112, 1298305253376, 6818128265216, 33772142067712, 178415166291968, 886967057252352 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 72*a(n-2) - 1712*a(n-4) + 13440*a(n-6).

Empirical g.f.: 4*x*(58 + 287*x - 2808*x^2 - 13828*x^3 + 33600*x^4 + 164640*x^5) / ((1 - 20*x^2)*(1 - 24*x^2)*(1 - 28*x^2)). - Colin Barker, Oct 16 2018

EXAMPLE

Some solutions for n=5:

..0..6....1..3....4..1....4..0....6..0....1..5....1..5....0..0....5..3....0..2

..1..2....4..1....4..6....5..6....1..0....5..4....6..5....0..5....1..4....5..2

..0..6....3..5....6..3....4..0....0..4....6..0....6..0....0..0....2..0....3..5

..5..6....4..1....4..6....3..4....5..4....5..4....4..3....1..6....3..6....3..0

..0..6....0..2....6..3....6..2....2..6....1..5....1..5....5..5....2..0....3..5

..5..6....6..3....0..2....3..4....6..5....1..0....4..3....0..5....2..5....6..3

CROSSREFS

Column 1 of A234690.

Sequence in context: A153466 A200870 A234690 * A238919 A327831 A234682

Adjacent sequences:  A234680 A234681 A234682 * A234684 A234685 A234686

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 29 2013

STATUS

approved

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Last modified October 15 18:54 EDT 2021. Contains 348034 sequences. (Running on oeis4.)