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%I #4 Feb 03 2014 05:30:13
%S 256,2132,2132,15882,51000,15882,128988,1046822,1046822,128988,
%T 1042300,23830240,53940782,23830240,1042300,8613338,540277188,
%U 3263989086,3263989086,540277188,8613338,71747464,12551185804,195683299844
%N T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with the upper median of every 2X2 subblock equal
%C Table starts
%C .....256........2132..........15882............128988..............1042300
%C ....2132.......51000........1046822..........23830240............540277188
%C ...15882.....1046822.......53940782........3263989086.........195683299844
%C ..128988....23830240.....3263989086......540145357880.......88307088989348
%C .1042300...540277188...195683299844....88307088989348....39085052507056252
%C .8613338.12551185804.12159520038142.14967248359057988.17922505416903364948
%H R. H. Hardin, <a href="/A237076/b237076.txt">Table of n, a(n) for n = 1..180</a>
%F Empirical for column k:
%F k=1: [linear recurrence of order 12]
%F k=2: [order 26]
%F k=3: [order 62]
%e Some solutions for n=2 k=4
%e ..0..0..0..1..1....0..0..0..0..1....0..0..2..0..0....0..0..1..1..3
%e ..1..1..1..1..1....1..1..3..1..2....1..1..1..1..1....1..1..0..1..0
%e ..0..0..1..1..0....2..0..0..0..1....2..1..0..3..0....0..0..1..1..2
%K nonn,tabl
%O 1,1
%A _R. H. Hardin_, Feb 03 2014