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%I #5 Dec 17 2013 06:12:15
%S 224,1176,5984,34416,189632,1128928,6414208,38622656,222041856,
%T 1341849472,7749914112,46887986944,271306185728,1642034355712,
%U 9508544919552,57555613998080,333396836184064,2018143397804032
%N Number of (n+1)X(1+1) 0..7 arrays with every 2X2 subblock having the sum of the absolute values of all six edge and diagonal differences equal to 21
%C Column 1 of A233875
%H R. H. Hardin, <a href="/A233869/b233869.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +72*a(n-2) -136*a(n-3) -1764*a(n-4) +2984*a(n-5) +18928*a(n-6) -25920*a(n-7) -92800*a(n-8) +81920*a(n-9) +204800*a(n-10) -81920*a(n-11) -172032*a(n-12) +16384*a(n-13) +32768*a(n-14)
%e Some solutions for n=5
%e ..0..6....0..1....0..6....6..6....6..3....0..7....2..5....6..0....0..7....4..1
%e ..6..7....1..7....3..0....0..3....0..6....3..3....7..1....4..1....1..1....7..1
%e ..0..6....6..3....6..0....3..7....5..2....7..0....6..3....7..7....0..7....2..5
%e ..3..0....6..0....3..6....3..0....6..0....7..7....1..7....4..1....6..6....7..1
%e ..6..0....0..3....0..6....0..6....6..7....7..0....2..5....6..0....7..0....0..1
%e ..1..4....6..6....7..6....3..6....6..0....2..2....1..7....3..0....4..4....7..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 17 2013