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A234491 Number of (n+1) X (1+1) 0..5 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
250, 1834, 13464, 99142, 728536, 5368636, 39476802, 291119578, 2142048610, 15807820384, 116387461374, 859523654392, 6332338846996, 46797181439986, 344979511889562, 2551214650069978, 18818390917298920, 139260488424222934 (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) = 5*a(n-1) + 74*a(n-2) - 295*a(n-3) - 1008*a(n-4) + 840*a(n-5).

Empirical g.f.: 2*x*(125 + 292*x - 7103*x^2 - 15072*x^3 + 14760*x^4) / ((1 - 56*x^2)*(1 - 5*x - 18*x^2 + 15*x^3)). - Colin Barker, Oct 15 2018

EXAMPLE

Some solutions for n=4:

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

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

4 2 0 1 2 2 0 2 1 3 4 3 3 1 4 1 3 0 4 1

4 4 5 4 2 4 4 4 2 2 3 4 3 3 4 3 3 2 5 0

5 3 1 2 5 5 3 1 1 3 2 1 1 3 3 4 4 1 4 1

CROSSREFS

Column 1 of A234497.

Sequence in context: A045185 A122270 A234497 * A249199 A249214 A249321

Adjacent sequences: A234488 A234489 A234490 * A234492 A234493 A234494

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 26 2013

STATUS

approved

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Last modified January 28 14:40 EST 2023. Contains 359895 sequences. (Running on oeis4.)