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%I #8 Aug 09 2018 08:56:15
%S 8,180,3760,64324,1043774,16758008,268358624,4294659968,68718247424,
%T 1099506710528,17592166375424,281474898034688,4503599312666624,
%U 72057592779112448,1152921499571585024,18446744053568503808
%N Equals one maps: number of n X 4 binary arrays indicating the locations of corresponding elements equal to exactly one of their king-move neighbors in a random 0..3 n X 4 array.
%C Column 4 of A221590.
%H R. H. Hardin, <a href="/A221589/b221589.txt">Table of n, a(n) for n = 1..92</a>
%F Empirical: a(n) = 20*a(n-1) -64*a(n-2) for n>6.
%F Conjectures from _Colin Barker_, Aug 09 2018: (Start)
%F G.f.: 2*x*(4 + 10*x + 336*x^2 + 322*x^3 - 1033*x^4 - 368*x^5) / ((1 - 4*x)*(1 - 16*x)).
%F a(n) = 16^n - 2401*2^(2*n-9) for n>4.
%F (End)
%e Some solutions for n=3.
%e ..1..0..0..1....0..0..0..0....0..0..0..1....0..0..1..1....0..0..0..1
%e ..0..0..1..1....0..0..0..1....1..0..0..1....0..1..1..1....1..1..1..0
%e ..0..1..1..0....0..1..0..0....0..1..1..0....0..0..0..1....1..0..1..0
%Y Cf. A221590.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 20 2013
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