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%I #8 Dec 23 2018 08:56:15
%S 66,158,214,462,676,1374,2040,4104,6136,12296,18424,36872,55288,
%T 110600,165880,331784,497656,995336,1492984,2985992,4478968,8957960,
%U 13436920,26873864,40310776,80621576,120932344,241864712,362797048,725594120
%N Number of (n+2) X (1+2) 0..1 arrays with no 3 X 3 subblock diagonal sum 0 and no antidiagonal sum 3 and no row sum 0 or 3 and no column sum 0 or 3.
%H R. H. Hardin, <a href="/A258959/b258959.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = -a(n-1) + 3*a(n-2) + 3*a(n-3) for n>9.
%F Empirical g.f.: 2*x*(33 + 112*x + 87*x^2 + 2*x^3 + 11*x^4 + 11*x^5 - 3*x^7 - x^8) / ((1 + x)*(1 - 3*x^2)). - _Colin Barker_, Dec 23 2018
%e Some solutions for n=4:
%e ..1..1..0....1..0..1....0..0..1....0..0..1....1..0..1....0..1..1....0..1..0
%e ..1..0..0....1..1..0....1..0..0....1..1..0....1..1..0....1..0..0....1..0..1
%e ..0..1..1....0..0..1....0..1..1....0..1..0....0..1..0....0..0..1....1..0..1
%e ..1..0..0....1..0..0....1..0..0....1..0..1....1..0..1....1..1..0....0..1..0
%e ..0..1..1....0..1..1....0..1..1....0..0..1....1..0..1....0..1..0....0..1..1
%e ..0..0..1....1..0..0....0..1..1....0..1..0....0..1..0....0..0..1....1..0..0
%Y Column 1 of A258966.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jun 15 2015
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