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%I #7 Jul 23 2018 13:43:49
%S 3,17,77,343,1523,6761,30013,133231,591427,2625409,11654477,51735495,
%T 229659507,1019483609,4525598973,20089627615,89180048899,395879967217,
%U 1757354367693,7801087777591,34629879796851,153725814775369
%N Number of n X 2 arrays of the minimum value of corresponding elements and their horizontal or antidiagonal neighbors in a random 0..2 n X 2 array.
%C Column 2 of A217964.
%H R. H. Hardin, <a href="/A217958/b217958.txt">Table of n, a(n) for n = 1..179</a>
%F Empirical: a(n) = 4*a(n-1) + 2*a(n-2) - a(n-4).
%F Empirical g.f.: x*(1 + x)*(3 + 2*x + x^2) / (1 - 4*x - 2*x^2 + x^4). - _Colin Barker_, Jul 23 2018
%e Some solutions for n=3:
%e ..0..0....0..0....2..2....1..0....2..1....1..1....2..2....2..1....2..2....0..0
%e ..0..0....1..2....2..2....0..0....1..0....2..2....2..2....1..1....1..0....0..2
%e ..0..2....1..1....0..0....0..2....0..0....1..1....2..2....0..0....0..0....2..2
%Y Cf. A217964.
%K nonn
%O 1,1
%A _R. H. Hardin_, Oct 16 2012
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