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%I #7 May 18 2020 19:25:19
%S 1,877,27644437,27700815674032,196551307092757144384,
%T 5737167377815628378510929822,510275358863420934339418249390485008,
%U 114130286115375064054502412158789812265958284,56140177561453730943968268473396800731088097525712216
%N Number of 7 X n nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to any horizontal or antidiagonal neighbor (colorings ignoring permutations of colors).
%H Andrew Howroyd, <a href="/A208307/b208307.txt">Table of n, a(n) for n = 0..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 ..0..1..0..1....0..1..0..1....0..1..2..0....0..1..0..1....0..1..0..1
%e ..0..1..0..1....0..1..0..1....0..1..2..0....0..1..0..1....0..1..0..1
%e ..2..1..0..1....0..1..0..1....0..1..2..0....0..1..0..1....0..1..0..1
%e ..0..1..2..0....0..1..0..1....0..1..2..0....0..1..0..1....0..1..0..1
%e ..0..1..2..1....2..1..0..1....0..1..2..0....0..1..0..1....0..2..0..1
%e ..0..1..0..1....0..1..0..1....0..1..2..0....0..1..0..1....0..1..0..1
%Y Row 7 of A208301.
%K nonn
%O 0,2
%A _R. H. Hardin_ Feb 25 2012
%E a(0)=1 prepended and terms a(6) and beyond from _Andrew Howroyd_, May 18 2020