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A234697 Number of (n+1) X (1+1) 0..7 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
408, 2628, 16848, 109224, 704160, 4594320, 29782080, 195532704, 1274237568, 8416415808, 55124437248, 366185867904, 2409750673920, 16093719394560, 106373608473600, 713965515692544, 4738136283260928, 31947371388453888 (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) = 6*a(n-1) + 90*a(n-2) - 540*a(n-3) - 2016*a(n-4) + 12096*a(n-5).

Empirical g.f.: 12*x*(34 + 15*x - 2970*x^2 - 672*x^3 + 64512*x^4) / ((1 - 6*x)*(1 - 42*x^2)*(1 - 48*x^2)). - Colin Barker, Oct 16 2018

EXAMPLE

Some solutions for n=4:

..7..7....7..2....7..2....5..4....5..2....1..7....4..0....2..5....4..3....6..0

..0..5....0..0....7..7....3..7....0..2....0..1....6..7....5..3....0..4....1..0

..7..7....6..1....2..7....7..6....6..3....4..0....0..6....1..4....1..0....2..6

..5..0....5..5....0..0....3..7....1..3....0..1....5..6....6..4....3..7....6..5

..7..7....1..6....6..1....5..4....7..4....5..1....4..0....0..3....7..6....0..4

CROSSREFS

Column 1 of A234702.

Sequence in context: A067674 A157263 A234702 * A337795 A183717 A285767

Adjacent sequences:  A234694 A234695 A234696 * A234698 A234699 A234700

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 29 2013

STATUS

approved

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Last modified May 26 21:56 EDT 2022. Contains 354092 sequences. (Running on oeis4.)