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%I #8 Jun 25 2017 17:19:43
%S 5,203,83440,112073062,346212384169,2043836452962923,
%T 20538493062072286871,324446721789278481458200,
%U 7600607444778834885508561198,252518539060608935260165703671351,11485037650037932819944784728914383376,694873103685620467779932914106484450991930
%N Number of n X 4 nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to any horizontal, vertical or antidiagonal neighbor (colorings ignoring permutations of colors).
%H Andrew Howroyd, <a href="/A208052/b208052.txt">Table of n, a(n) for n = 1..50</a>
%e Some solutions for n=4
%e ..0..1..0..1....0..1..0..1....0..1..0..1....0..1..0..1....0..1..0..1
%e ..2..3..2..0....2..3..2..3....2..3..2..0....2..3..2..0....2..3..2..0
%e ..4..0..1..2....0..1..0..2....4..0..1..2....0..1..3..1....0..1..3..1
%e ..1..2..3..0....2..3..1..0....1..2..0..3....4..0..5..0....2..4..0..2
%Y Column 4 of A208054.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 22 2012
%E Terms a(11) and beyond from _Andrew Howroyd_, Jun 25 2017
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