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Number of (n+1) X 8 0..2 arrays with all 2 X 2 subblock sums the same.
1

%I #8 Apr 09 2018 14:53:20

%S 13225,15555,19217,26655,39697,66591,118097,227319,453025,954495,

%T 2073857,4730055,11163217,27594351,70508657,187283319,510129025,

%U 1427563935,4057091297,11721369255,34143669937,100392943311,296377454417

%N Number of (n+1) X 8 0..2 arrays with all 2 X 2 subblock sums the same.

%C Column 7 of A184003.

%H R. H. Hardin, <a href="/A184001/b184001.txt">Table of n, a(n) for n = 1..107</a>

%F Empirical: a(n) = 6*a(n-1) - 60*a(n-3) + 85*a(n-4) + 150*a(n-5) - 360*a(n-6) + 396*a(n-8) - 216*a(n-9).

%F Empirical g.f.: x*(13225 - 63795*x - 74113*x^2 + 704853*x^3 - 311058*x^4 - 2324496*x^5 + 2112156*x^6 + 2352132*x^7 - 2606904*x^8) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 2*x^2)*(1 - 3*x^2)*(1 - 6*x^2)). - _Colin Barker_, Apr 09 2018

%e Some solutions for 3 X 8:

%e ..1..1..1..0..2..0..2..0....2..0..1..2..1..0..1..2....2..2..0..2..0..2..0..1

%e ..1..0..1..1..0..1..0..1....1..2..2..0..2..2..2..0....0..0..2..0..2..0..2..1

%e ..0..2..0..1..1..1..1..1....2..0..1..2..1..0..1..2....2..2..0..2..0..2..0..1

%Y Cf. A184003.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 08 2011