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%I #8 Oct 04 2018 11:50:32
%S 3,37,257,1915,14223,105411,781873,5798587,43004317,318935945,
%T 2365343683,17542244471,130099628443,964865884537,7155794283827,
%U 53069957831125,393585996554193,2918976065097931,21648181955586463,160550745032206387
%N Number of n X 2 0..2 arrays with every 0 next to a 1 and every 1 next to a 2 horizontally, vertically or antidiagonally.
%H R. H. Hardin, <a href="/A232303/b232303.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) + 9*a(n-2) + 11*a(n-3) - a(n-4) + 16*a(n-5).
%F Empirical g.f.: x*(3 + 19*x + 8*x^2 + 7*x^3 + 16*x^4) / (1 - 6*x - 9*x^2 - 11*x^3 + x^4 - 16*x^5). - _Colin Barker_, Oct 04 2018
%e Some solutions for n=6:
%e ..2..1....0..1....2..1....2..2....1..2....1..2....2..1....2..2....0..1....0..2
%e ..0..0....1..2....2..1....1..1....0..2....2..1....0..0....0..0....1..2....1..0
%e ..0..0....2..1....1..1....0..1....1..0....0..1....2..0....1..1....0..2....1..1
%e ..1..1....2..1....2..1....2..2....1..1....0..2....1..0....2..1....2..1....2..1
%e ..2..2....0..2....1..1....2..1....2..0....0..0....1..0....1..0....2..2....0..2
%e ..1..2....1..2....2..1....0..2....1..2....1..2....2..2....2..2....2..2....0..1
%Y Column 2 of A232309.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 22 2013
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