%I #6 Dec 18 2015 18:17:40
%S 0,1,5,120,7335,1156521,457780079,457756056728,1154866876506535,
%T 7352987974445171007,118143153320894808308264,
%U 4790379823545169735782598423,490170667588709471795216706934694
%N Number of n X n symmetric 0..2 arrays with each element equal to at least one horizontal or vertical neighbor and any new values 0..2 introduced in lower triangular row major order
%e Some solutions for 6X6 containing a 2
%e ..0..0..0..2..2..1....0..0..0..1..1..2....0..0..0..0..2..0....0..0..0..0..0..0
%e ..0..0..0..0..2..1....0..0..0..2..2..2....0..0..0..1..2..0....0..0..0..0..2..2
%e ..0..0..1..1..2..2....0..0..1..1..2..0....0..0..0..1..0..0....0..0..0..1..1..2
%e ..2..0..1..0..0..0....1..2..1..2..2..0....0..1..1..2..2..1....0..0..1..0..0..1
%e ..2..2..2..0..1..1....1..2..2..2..2..0....2..2..0..2..2..1....0..2..1..0..1..1
%e ..1..1..2..0..1..1....2..2..0..0..0..0....0..0..0..1..1..1....0..2..2..1..1..1
%K nonn
%O 1,3
%A _R. H. Hardin_ Jul 06 2011
|