%I #4 Dec 17 2013 16:10:03

%S 160,640,2440,9612,36976,145004,559736,2189924,8470344,33088100,

%T 128155456,500055876,1938715672,7558416852,29325538832,114258452900,

%U 443550616168,1727342374724,6708320872096,26115152683348,101452849075768

%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 30, and no two adjacent values equal

%C Column 1 of A233917

%H R. H. Hardin, <a href="/A233910/b233910.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 24*a(n-2) +6*a(n-3) -177*a(n-4) -52*a(n-5) +516*a(n-6) +80*a(n-7) -646*a(n-8) +42*a(n-9) +284*a(n-10) -80*a(n-11)

%e Some solutions for n=5

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 17 2013