%I #9 Jul 07 2014 11:14:48
%S 210,18792,5422402,5243407780,16720419105846,176072290483114471,
%T 6123962812371625570408
%N Half the number of (n+2) X (n+2) binary arrays with each 3 X 3 subblock having sum 3, 4, 5 or 6.
%C Diagonal of A187317.
%e Some solutions for 4 X 4 with a(1,1)=0:
%e ..0..1..1..0....0..1..0..1....0..1..1..1....0..0..0..1....0..0..1..0
%e ..1..0..0..1....0..0..0..1....1..0..0..0....0..1..0..0....0..0..1..1
%e ..1..1..0..1....1..0..1..0....1..1..1..0....1..0..1..0....1..1..0..0
%e ..1..1..1..0....1..0..0..1....1..1..0..0....0..0..1..1....0..0..1..0
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 08 2011
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