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A234550 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 3 (constant stress 1 X 1 tilings). 1
360, 2716, 20416, 153752, 1157728, 8726336, 65777344, 496308128, 3744934912, 28286490944, 213660702976, 1615562611712, 12215896488448, 92467959109376, 699922909794304, 5303754118235648, 40188257800148992, 304858331817979904 (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) = 118*a(n-2) - 3660*a(n-4) + 10800*a(n-6).

Empirical g.f.: 4*x*(90 + 679*x - 5516*x^2 - 41684*x^3 + 16560*x^4 + 131040*x^5) / ((1 - 60*x^2)*(1 - 58*x^2 + 180*x^4)). - Colin Barker, Oct 15 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

CROSSREFS

Column 1 of A234555.

Sequence in context: A056390 A056380 A234555 * A024185 A033592 A305626

Adjacent sequences:  A234547 A234548 A234549 * A234551 A234552 A234553

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 28 2013

STATUS

approved

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Last modified December 7 06:04 EST 2021. Contains 349567 sequences. (Running on oeis4.)