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%I #8 Dec 20 2018 23:07:15
%S 32,86,237,641,1731,4690,12707,34408,93168,252313,683305,1850413,
%T 5011000,13570213,36749148,99519030,269504389,729837077,1976449263,
%U 5352360678,14494564867,39252288748,106297917568,287862131449,779550625853
%N Number of (n+2) X (1+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 0 and no antidiagonal sum 0 and no row sum 0 or 1 and no column sum 0 or 1.
%H R. H. Hardin, <a href="/A256803/b256803.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + a(n-2) + 7*a(n-3) + 7*a(n-4) + 3*a(n-5) - a(n-6) - 6*a(n-7) - 2*a(n-8).
%F Empirical g.f.: x*(32 + 54*x + 119*x^2 + 94*x^3 + 27*x^4 - 39*x^5 - 86*x^6 - 26*x^7) / (1 - x - x^2 - 7*x^3 - 7*x^4 - 3*x^5 + x^6 + 6*x^7 + 2*x^8). - _Colin Barker_, Dec 20 2018
%e Some solutions for n=4:
%e ..1..0..1....0..1..1....1..1..1....1..1..1....1..0..1....1..1..0....0..1..1
%e ..1..1..1....1..1..1....1..0..1....1..0..1....1..1..1....1..1..1....1..1..0
%e ..0..1..1....1..0..1....0..1..1....1..1..0....1..1..1....1..1..1....1..1..1
%e ..1..1..1....1..1..1....1..1..0....1..1..1....1..1..1....1..1..1....0..1..1
%e ..1..1..0....0..1..1....1..1..1....0..1..1....1..1..0....0..1..1....1..1..1
%e ..1..1..1....1..1..1....0..1..1....1..1..1....1..1..1....1..1..0....1..1..1
%Y Column 1 of A256810.
%K nonn
%O 1,1
%A _R. H. Hardin_, Apr 10 2015
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