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%I #11 Sep 12 2018 07:52:05
%S 8,12,140,416,2844,11148,62368,275708,1420076,6614240,32897116,
%T 156718796,767930400,3694025404,17985757548,86879470432,421850136604,
%U 2041379040012,9900460336800,47946203889788,232416817429420,1125924852017632
%N Number of 4 X n binary arrays with top left value 1 and no two ones adjacent horizontally, diagonally or antidiagonally.
%H R. H. Hardin, <a href="/A228663/b228663.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) + 16*a(n-2) - 7*a(n-3) - 18*a(n-4).
%F Empirical g.f.: 4*x*(1 + x)*(2 - 3*x) / (1 - 2*x - 16*x^2 + 7*x^3 + 18*x^4). - _Colin Barker_, Sep 12 2018
%e Some solutions for n=4:
%e ..1..0..0..1....1..0..1..0....1..0..0..1....1..0..0..0....1..0..0..1
%e ..0..0..0..0....0..0..0..0....1..0..0..1....0..0..1..0....0..0..0..0
%e ..0..0..0..0....1..0..0..1....0..0..0..0....0..0..0..0....0..0..0..1
%e ..0..1..0..0....1..0..0..0....0..0..0..0....1..0..0..1....1..0..0..0
%Y Row 4 of A228660.
%K nonn
%O 1,1
%A _R. H. Hardin_, Aug 29 2013
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