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%I #6 Dec 18 2015 18:17:42
%S 1,2,32,1544,176621,47206184,29472402866,42983827798496,
%T 146444618198769125,1165528963636440929600,21669813287735290595660642,
%U 941174635410204103533009279920,95492317441878732465782043745326917
%N Number of n X n symmetric 0..3 arrays with no element equal to any horizontal or vertical neighbor and with new values 0..3 introduced in lower triangular row major order
%H R. H. Hardin, <a href="/A193269/b193269.txt">Table of n, a(n) for n = 1..15</a>
%e Some solutions for 4X4
%e ..0..1..2..1....0..1..0..3....0..1..2..3....0..1..0..3....0..1..2..3
%e ..1..0..3..0....1..2..3..0....1..0..3..1....1..0..1..2....1..2..3..2
%e ..2..3..0..2....0..3..2..1....2..3..2..0....0..1..2..3....2..3..1..3
%e ..1..0..2..3....3..0..1..2....3..1..0..1....3..2..3..2....3..2..3..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Jul 20 2011
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