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Number of (n+1) X 8 0..2 arrays with every 2 X 2 subblock having the same number of clockwise edge increases as its horizontal neighbors and the same number of counterclockwise edge increases as its vertical neighbors.
1

%I #9 Nov 03 2022 21:45:17

%S 1112664,17051166,976932162,63265158237,4140502079766,274342874332980,

%T 18225426305218983,1214621133289445748,80992571869156601646,

%U 5405796006447301221615,360832630784933797787058

%N Number of (n+1) X 8 0..2 arrays with every 2 X 2 subblock having the same number of clockwise edge increases as its horizontal neighbors and the same number of counterclockwise edge increases as its vertical neighbors.

%C Column 7 of A205917.

%H R. H. Hardin, <a href="/A205916/b205916.txt">Table of n, a(n) for n = 1..14</a>

%e Some solutions for n=4:

%e ..0..2..0..2..0..0..1..2....0..0..0..1..0..0..1..1....2..1..2..1..2..1..1..2

%e ..2..2..2..2..2..0..1..2....2..2..0..0..0..1..1..2....2..1..2..1..1..1..2..2

%e ..0..2..1..2..0..0..1..1....2..0..0..1..0..1..2..2....1..1..1..1..0..1..1..1

%e ..0..2..1..2..0..1..1..2....0..0..1..1..0..1..1..2....0..1..0..0..0..0..0..1

%e ..0..2..1..2..0..0..1..1....1..1..1..0..0..1..2..2....0..0..0..1..0..1..1..1

%Y Cf. A205917.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 01 2012