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%I #13 May 18 2020 03:01:23
%S 1,5,377,169064,235862938,746823293346,4493602584256529,
%T 45881957995776221396,734971289403287420883126,
%U 17434398033181126785548889533,585880828202059360820577364423099,26929433656271781956071918468836389588,1645382407173932261418519657416983542506695
%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, diagonal or antidiagonal neighbor (colorings ignoring permutations of colors).
%H Andrew Howroyd, <a href="/A208094/b208094.txt">Table of n, a(n) for n = 0..100</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 ..0..1..0..2....0..1..0..1....0..1..2..1....0..1..0..1....0..1..0..2
%e ..2..1..0..1....2..1..0..2....0..1..0..1....0..2..0..1....2..1..0..1
%e ..0..1..2..1....0..1..0..1....0..1..0..1....0..1..0..1....0..1..0..2
%Y Column 4 of A208096.
%K nonn
%O 0,2
%A _R. H. Hardin_, Feb 23 2012
%E a(0)=1 prepended and terms a(8) and beyond from _Andrew Howroyd_, May 17 2020
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