%I #4 Mar 31 2012 12:37:34
%S 1,3,35,792,34547,2902490,468761578,145469326676,86673425993599
%N Number of (2n)X(2n) 0..2 symmetric matrices with every element equal to two horizontal and vertical neighbors, and new values 0..2 introduced in lower triangle row major order
%e All solutions for n=2
%e ..0..0..0..0....0..0..1..1....0..0..1..1
%e ..0..1..1..0....0..0..1..1....0..0..1..1
%e ..0..1..1..0....1..1..2..2....1..1..0..0
%e ..0..0..0..0....1..1..2..2....1..1..0..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Mar 29 2012
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