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Number of (n+1) X 8 0..1 arrays with the number of clockwise edge increases in every 2 X 2 subblock differing from each horizontal or vertical neighbor.
1

%I #8 Jun 11 2018 04:18:33

%S 432,440,708,864,1568,2048,3904,4608,7872,9216,15808,18944,32960,

%T 39936,69824,84480,147520,178176,310848,375296,654656,790528,1379136,

%U 1665536,2905792,3509248,6122432,7393792,12899520,15578112,27178176,32821760

%N Number of (n+1) X 8 0..1 arrays with the number of clockwise edge increases in every 2 X 2 subblock differing from each horizontal or vertical neighbor.

%C Column 7 of A205193.

%H R. H. Hardin, <a href="/A205192/b205192.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-2) +a(n-8) for n>13.

%F Empirical g.f.: 4*x*(108 + 110*x - 39*x^2 - 4*x^3 + 38*x^4 + 80*x^5 + 192*x^6 + 128*x^7 - 92*x^8 - 110*x^9 - 161*x^10 - 88*x^11 - 56*x^12) / (1 - 2*x^2 - x^8). - _Colin Barker_, Jun 11 2018

%e Some solutions for n=4:

%e ..0..0..1..1..0..0..1..1....1..0..0..1..0..0..1..1....1..0..0..1..1..0..0..1

%e ..1..1..0..0..1..1..0..0....0..1..1..0..0..0..1..1....0..1..1..0..0..1..1..0

%e ..1..1..0..0..1..1..0..0....0..1..1..0..0..1..0..0....1..1..1..0..0..1..1..0

%e ..1..0..1..1..0..0..1..1....1..0..0..1..1..0..0..0....1..1..0..1..1..0..0..1

%e ..0..1..1..1..0..0..1..1....0..0..0..1..1..0..0..1....0..0..1..1..1..0..0..0

%Y Cf. A205193.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 23 2012