%I #5 Mar 31 2012 12:37:04
%S 98,90,144,220,347,524,850,1268,2048,3060,4942,7388,11938,17836,28826,
%T 43060,69621,103956,168108,250972,405913,605900,980086,1462772,
%U 2366374,3531444,5713346,8525660,13794016,20582764,33303134,49691188,80403523
%N Number of (n+1)X4 0..1 arrays with the number of rightwards and downwards edge increases in each 2X2 subblock differing from the number in all its horizontal and vertical neighbors
%C Column 3 of A205072
%H R. H. Hardin, <a href="/A205067/b205067.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-2) -2*a(n-6) -2*a(n-8) -4*a(n-10) +2*a(n-14) +3*a(n-16) +a(n-18) for n>20
%e Some solutions for n=4
%e ..1..0..0..1....1..1..0..1....0..0..0..1....0..1..1..1....0..0..1..1
%e ..0..1..0..1....0..1..0..0....0..1..0..1....1..1..0..1....0..0..0..0
%e ..0..0..0..0....0..1..1..1....0..0..0..0....1..1..1..0....1..0..1..0
%e ..0..1..0..1....0..0..0..1....0..1..0..1....0..1..1..1....0..0..0..1
%e ..0..0..0..0....0..1..0..1....0..0..0..0....1..0..1..1....1..0..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 21 2012
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