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%I #6 Dec 18 2015 18:17:42
%S 1,2,42,10455,17957112,139031457162,4542089826393987,
%T 623345036311461259086,359303834921251677870936120,
%U 869870085407321787861592624745847
%N Number of n X n symmetric 0..5 arrays with no element equal to any horizontal or vertical neighbor and with new values 0..5 introduced in lower triangular row major order
%H R. H. Hardin, <a href="/A193271/b193271.txt">Table of n, a(n) for n = 1..11</a>
%e Some solutions for 4X4
%e ..0..1..2..3....0..1..0..2....0..1..3..2....0..1..3..2....0..1..2..1
%e ..1..2..0..2....1..2..3..5....1..2..0..1....1..2..4..1....1..2..0..4
%e ..2..0..2..0....0..3..4..1....3..0..4..2....3..4..3..0....2..0..3..2
%e ..3..2..0..2....2..5..1..5....2..1..2..0....2..1..0..5....1..4..2..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Jul 20 2011