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%I #5 Feb 02 2014 07:35:51
%S 256,1200,5288,26320,131280,677344,3518120,18477584,97461616,
%T 516386016,2742670088,14598685968,77817078928,415298087392,
%U 2218380038504,11858851965712,63433486272944,339491529596384,1817787857754056
%N Number of (n+1)X(1+1) 0..3 arrays with the upper median plus the lower median of every 2X2 subblock equal
%C Column 1 of A237007
%H R. H. Hardin, <a href="/A237000/b237000.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 13*a(n-1) -21*a(n-2) -329*a(n-3) +1031*a(n-4) +3487*a(n-5) -13091*a(n-6) -21599*a(n-7) +79282*a(n-8) +90220*a(n-9) -248320*a(n-10) -246896*a(n-11) +371200*a(n-12) +361344*a(n-13) -192000*a(n-14) -184320*a(n-15)
%e Some solutions for n=5
%e ..2..2....1..2....1..3....1..3....0..1....0..3....2..0....2..1....2..3....0..3
%e ..3..1....1..2....2..1....0..3....2..1....1..3....2..1....2..1....2..2....2..1
%e ..3..0....1..3....2..1....1..3....0..1....3..1....2..1....1..2....2..1....0..2
%e ..2..2....2..1....1..3....1..3....1..2....2..2....3..1....2..0....2..2....2..1
%e ..2..2....2..1....2..0....2..2....1..0....2..2....2..1....1..3....3..0....2..1
%e ..3..1....2..1....2..1....2..1....3..1....1..3....1..3....2..0....3..1....2..0
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 02 2014