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Number of (n+1) X (5+1) 0..3 arrays with every 2 X 2 subblock having the sum of the absolute values of all six edge and diagonal differences equal to 9.
1

%I #11 Oct 13 2018 11:53:11

%S 1280,1544,1992,2984,4904,9512,19368,45224,104360,271784,670632,

%T 1861544,4764584,13716392,35808168,105157544,277398440,823206824,

%U 2183234472,6513902504,17322673064,51825116072,138009772968,413458301864

%N Number of (n+1) X (5+1) 0..3 arrays with every 2 X 2 subblock having the sum of the absolute values of all six edge and diagonal differences equal to 9.

%H R. H. Hardin, <a href="/A234137/b234137.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) + 8*a(n-2) - 30*a(n-3) + 4*a(n-4) + 48*a(n-5) - 32*a(n-6).

%F Empirical g.f.: 8*x*(160 - 287*x - 1610*x^2 + 2882*x^3 + 2652*x^4 - 4616*x^5) / ((1 - x)*(1 - 2*x)*(1 - 2*x^2)*(1 - 8*x^2)). - _Colin Barker_, Oct 13 2018

%e Some solutions for n=5:

%e 3 3 3 0 0 3 3 0 3 3 3 3 0 3 0 3 0 3 3 0 3 0 3 0

%e 3 0 3 3 0 0 0 0 0 3 0 3 0 0 0 0 0 0 1 1 1 1 1 1

%e 3 3 3 0 0 3 0 3 0 0 0 0 0 3 0 3 0 3 0 3 0 3 0 3

%e 3 0 3 3 0 0 0 0 0 3 0 3 2 2 2 2 2 2 0 0 0 0 0 0

%e 3 3 3 0 0 3 0 3 0 0 0 0 0 3 0 3 0 3 3 0 3 0 3 0

%e 3 0 3 3 0 0 0 0 0 3 0 3 1 1 1 1 1 1 3 3 3 3 3 3

%Y Column 5 of A234140.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 19 2013