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%I #8 Jun 01 2018 14:18:41
%S 4,50,398,3018,23436,182430,1417772,11017196,85621362,665418194,
%T 5171353118,40189602848,312336995590,2427354106352,18864392868124,
%U 146606264807250,1139363300400646,8854660691296250,68814763405175276
%N Number of n X 3 binary arrays with every one adjacent to another one horizontally, diagonally, antidiagonally or vertically.
%C Column 3 of A202795.
%H R. H. Hardin, <a href="/A202790/b202790.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) +2*a(n-2) +29*a(n-3) +16*a(n-4).
%F Empirical g.f.: 2*x*(2 + 11*x + 20*x^2 + 8*x^3) / (1 - 7*x - 2*x^2 - 29*x^3 - 16*x^4). - _Colin Barker_, Jun 01 2018
%e Some solutions for n=5:
%e ..1..0..1....1..0..0....1..0..0....1..1..0....1..1..0....1..1..1....0..1..0
%e ..1..1..0....0..1..0....1..1..0....1..0..1....1..0..1....1..0..0....0..1..1
%e ..0..1..0....1..1..0....1..1..1....1..1..0....1..1..0....1..1..1....1..1..0
%e ..1..1..0....0..1..0....0..1..0....1..1..0....1..1..1....1..1..0....1..1..0
%e ..0..0..1....0..1..0....1..0..0....0..1..0....1..0..0....0..1..0....0..1..1
%Y Cf. A202795.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 24 2011
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