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Number of (n+1)X(1+1) 0..7 arrays with every 2X2 subblock having the sum of the squares of the edge differences equal to 26
1

%I #5 Dec 15 2013 05:57:47

%S 280,1820,11016,68828,423220,2624872,16201200,100277820,619644916,

%T 3832773404,23693063108,146517647480,905857050536,5601325392044,

%U 34632490183556,214141349297724,1324043851903528,8186789590614456

%N Number of (n+1)X(1+1) 0..7 arrays with every 2X2 subblock having the sum of the squares of the edge differences equal to 26

%C Column 1 of A233724

%H R. H. Hardin, <a href="/A233718/b233718.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +58*a(n-2) -58*a(n-3) -1227*a(n-4) +461*a(n-5) +12296*a(n-6) +722*a(n-7) -62278*a(n-8) -22804*a(n-9) +155159*a(n-10) +90798*a(n-11) -162636*a(n-12) -121112*a(n-13) +35968*a(n-14) +28416*a(n-15) -1152*a(n-16)

%e Some solutions for n=4

%e ..5..6....6..7....3..4....3..0....5..5....4..4....0..4....1..3....1..4....2..2

%e ..5..2....3..7....7..4....5..2....6..2....3..7....1..1....3..6....3..1....3..6

%e ..5..1....6..6....4..6....5..1....5..2....6..6....5..4....3..7....6..3....2..6

%e ..4..1....2..5....1..4....5..2....3..0....2..5....1..4....3..6....4..1....3..6

%e ..2..4....5..3....4..6....6..6....3..4....5..7....5..4....5..3....5..1....1..3

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 15 2013