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%I #10 May 18 2020 18:58:50
%S 1,15,500,192328,235862938,677352910013,3773408294000427,
%T 36179066767453804155,549736601190850705047301,
%U 12463226118187748082979153202,402612019211536786633308878052340,17870804510325656079748707416649732732,1058340866272922899343613575761029687845720
%N Number of 4 X n 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="/A208099/b208099.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..1....0..1..0..2....0..1..0..1....2..1..0..1....2..1..0..1
%e ..0..1..2..1....2..1..0..1....2..1..0..2....0..3..0..1....0..1..2..1
%e ..0..1..3..1....0..1..0..2....0..1..0..1....4..1..0..1....0..1..0..1
%Y Row 4 of A208096.
%K nonn
%O 0,2
%A _R. H. Hardin_, Feb 23 2012
%E a(0)=1 prepended and terms a(6) and beyond from _Andrew Howroyd_, May 18 2020
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