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%I #5 Feb 09 2014 05:48:42
%S 256,1692,11602,83104,598364,4364082,31944336,235256268,1738258026,
%T 12893878848,95919856580,715664084818,5352837879288,40130893138332,
%U 301489296666562,2269299751178560,17109984950539036,129203951232487378
%N Number of (n+1)X(1+1) 0..3 arrays with the upper median minus the lower median of every 2X2 subblock equal
%C Column 1 of A237538
%H R. H. Hardin, <a href="/A237532/b237532.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 18*a(n-1) -64*a(n-2) -539*a(n-3) +3795*a(n-4) +1414*a(n-5) -58056*a(n-6) +84851*a(n-7) +309622*a(n-8) -875960*a(n-9) -155176*a(n-10) +2621808*a(n-11) -2284736*a(n-12) -1589504*a(n-13) +3589120*a(n-14) -2039808*a(n-15) +393216*a(n-16)
%e Some solutions for n=4
%e ..2..0....1..1....2..1....2..3....2..1....3..0....3..2....0..1....1..1....1..2
%e ..0..1....0..1....1..2....3..2....3..0....1..0....2..0....2..0....1..0....0..2
%e ..2..3....2..1....0..2....2..3....1..2....2..0....3..2....1..2....1..1....1..0
%e ..3..2....1..1....0..1....2..3....2..1....2..1....2..0....0..0....0..1....2..0
%e ..2..3....0..2....3..2....2..3....3..1....2..1....0..0....1..1....3..1....1..2
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 09 2014