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%I #5 Dec 18 2015 18:17:40
%S 0,1,5,137,15055,5986313,7174532375,25969938730579,281423389721323932,
%T 9146849687492666154781,891167854920321677292610251
%N Number of n X n symmetric 0..3 arrays with each element equal to at least one horizontal or vertical neighbor and any new values 0..3 introduced in lower triangular row major order
%e Some solutions for 6X6 containing a 3
%e ..0..0..0..0..3..3....0..0..0..0..3..3....0..0..0..0..1..1....0..0..0..0..1..1
%e ..0..0..0..2..2..2....0..0..0..1..1..0....0..0..0..0..0..0....0..0..0..2..2..1
%e ..0..0..1..1..3..3....0..0..1..1..1..0....0..0..0..1..1..0....0..0..1..1..3..3
%e ..0..2..1..0..0..0....0..1..1..2..2..0....0..0..1..1..2..2....0..2..1..2..2..3
%e ..3..2..3..0..0..3....3..1..1..2..2..0....1..0..1..2..2..3....1..2..3..2..2..1
%e ..3..2..3..0..3..3....3..0..0..0..0..0....1..0..0..2..3..3....1..1..3..3..1..1
%K nonn
%O 1,3
%A _R. H. Hardin_ Jul 06 2011