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%I #8 Oct 20 2018 10:22:45
%S 294,722,1372,2660,5034,9752,18468,35794,67924,131474,251786,485354,
%T 926434,1789970,3433586,6602990,12649018,24390182,46809866,89947622,
%U 172622482,332388566,638104130,1225937510,2354814226,4530138566
%N Number of (n+1) X (2+1) 0..2 arrays colored with the upper median value of each 2 X 2 subblock.
%H R. H. Hardin, <a href="/A235948/b235948.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-3) + 10*a(n-4) - 12*a(n-7) - 6*a(n-8) for n>12.
%F Empirical g.f.: 2*x*(147 + 361*x + 686*x^2 + 889*x^3 - 36*x^4 - 792*x^5 - 1616*x^6 - 1190*x^7 - 622*x^8 - 327*x^9 - 62*x^10 + 5*x^11) / (1 - 3*x^3 - 10*x^4 + 12*x^7 + 6*x^8). - _Colin Barker_, Oct 20 2018
%e Some solutions for n=5:
%e ..0..2..1....1..0..0....1..0..0....2..0..1....1..2..2....2..2..1....1..2..1
%e ..2..1..0....2..1..0....1..0..1....1..2..0....0..0..2....0..0..0....2..1..0
%e ..0..0..0....1..2..0....0..0..2....0..1..2....1..0..1....2..1..0....0..0..0
%e ..0..1..2....0..0..0....2..1..2....0..0..0....2..0..0....1..2..1....0..1..2
%e ..1..2..1....0..2..1....2..0..0....2..1..0....2..1..2....0..0..2....0..2..1
%e ..2..1..0....1..0..2....1..1..0....2..1..0....1..0..2....0..1..0....2..1..0
%Y Column 2 of A235954.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 17 2014