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Number of (n+1) X 6 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 04:18:14

%S 144,168,292,384,736,896,1568,1920,3392,4224,7520,9344,16608,20608,

%T 36608,45440,80736,100224,178080,221056,392768,487552,866272,1075328,

%U 1910624,2371712,4214016,5230976,9294304,11537280,20499232,25446272,45212480

%N Number of (n+1) X 6 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 5 of A205193.

%H R. H. Hardin, <a href="/A205190/b205190.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-2) +a(n-6) for n>9.

%F Empirical g.f.: 4*x*(36 + 42*x + x^2 + 12*x^3 + 38*x^4 + 32*x^5 - 12*x^6 - 10*x^7 - 9*x^8) / (1 - 2*x^2 - x^6). - _Colin Barker_, Jun 11 2018

%e Some solutions for n=4:

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

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

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

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

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

%Y Cf. A205193.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 23 2012