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A183684 Number of (n+1) X 6 binary arrays with every 2 X 2 subblock nonsingular.

%I A183684 #10 Apr 04 2018 10:48:22
%S A183684 96,528,2688,14144,73344,382848,1992320,10382976,54072960,281700992,
%T A183684 1467309696,7643513472,39814841984,207399103104,1080347897472,
%U A183684 5627597738624,29314404685440,152700279978624,795423120883328
%N A183684 Number of (n+1) X 6 binary arrays with every 2 X 2 subblock nonsingular.
%C A183684 Column 5 of A183688.
%H A183684 R. H. Hardin, <a href="/A183684/b183684.txt">Table of n, a(n) for n = 1..200</a>
%F A183684 Empirical: a(n) = 3*a(n-1) + 18*a(n-2) - 20*a(n-3) - 72*a(n-4).
%F A183684 Empirical g.f.: 16*x*(6 + 15*x - 39*x^2 - 94*x^3) / ((1 + 2*x)*(1 - 5*x - 8*x^2 + 36*x^3)). - _Colin Barker_, Apr 04 2018
%e A183684 Some solutions for 3 X 6:
%e A183684 ..0..1..1..0..1..0....1..0..1..1..0..1....0..1..0..1..0..1....1..1..0..1..1..0
%e A183684 ..1..0..1..1..1..1....0..1..0..1..1..0....1..1..1..1..1..0....1..0..1..0..1..1
%e A183684 ..0..1..1..0..1..0....1..0..1..0..1..1....0..1..0..1..0..1....0..1..1..1..1..0
%Y A183684 Cf. A183688.
%K A183684 nonn
%O A183684 1,1
%A A183684 _R. H. Hardin_, Jan 06 2011