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%I #6 Dec 18 2015 18:18:47
%S 1,8,2688,10674176,406142844928,145451790488305664,
%T 491056502853059022422016,15650767090419537715133256040448,
%U 4713550152014576979763161453081103695872
%N Number of n X n 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally or vertically, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabelled 6-colorings with no clashing color pairs)
%C Diagonal of A233129
%H R. H. Hardin, <a href="/A233122/b233122.txt">Table of n, a(n) for n = 1..13</a>
%e Some solutions for n=3
%e ..0..1..0....0..1..2....0..1..0....0..1..2....0..1..2....0..1..2....0..1..2
%e ..1..5..1....2..5..4....1..5..2....4..2..4....1..2..1....3..0..1....4..3..0
%e ..2..1..2....5..2..5....2..1..0....5..1..0....3..0..2....0..1..5....5..1..3
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 04 2013
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