A185834 - OEIS

%I #7 Mar 31 2012 12:36:03

%S 13,1103,17877,257050,4143707,68363184,1073661088,17200095426,

%T 278159538826,4418356392225,71020967453692,1136704302337236,

%U 18204389915482609,291581361291318489,4670236803825684178

%N Half the number of nX8 binary arrays with every element equal to exactly one or two of its horizontal and vertical neighbors

%C Column 8 of A185835

%H R. H. Hardin, <a href="/A185834/b185834.txt">Table of n, a(n) for n = 1..101</a>

%e Some solutions for 4X8 with a(1,1)=0

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 05 2011