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A208045 Number of n X n 0..3 arrays with new values 0..3 introduced in row major order and no element equal to any horizontal, vertical or antidiagonal neighbor (colorings ignoring permutations of colors).

%I A208045 #10 Jun 02 2025 07:42:36
%S A208045 1,2,44,1904,168096,30818432,11838995200,9578237457408,
%T A208045 16372889877477376,59262411624914853888,454901302416508366209024,
%U A208045 7413673375795915677473636352
%N A208045 Number of n X n 0..3 arrays with new values 0..3 introduced in row major order and no element equal to any horizontal, vertical or antidiagonal neighbor (colorings ignoring permutations of colors).
%C A208045 Diagonal of A208050
%e A208045 Some solutions for n=4
%e A208045 ..0..1..2..1....0..1..2..1....0..1..2..3....0..1..0..1....0..1..2..1
%e A208045 ..2..0..3..2....2..3..0..3....3..0..1..0....2..3..2..3....2..3..0..2
%e A208045 ..3..2..1..0....0..1..2..0....1..2..3..1....0..1..0..1....0..2..1..3
%e A208045 ..0..3..2..1....2..3..1..3....3..1..0..2....2..3..2..0....1..0..2..1
%t A208045 A208050 = Cases[Import["https://oeis.org/A208050/b208050.txt", "Table"], {_, _}][[All, 2]];
%t A208045 a[n_] := A208050[[2 n^2 - 2 n + 1]];
%t A208045 Table[a[n], {n, 1, 12}] (* _Jean-François Alcover_, Sep 23 2019 *)
%K A208045 nonn
%O A208045 1,2
%A A208045 _R. H. Hardin_ Feb 22 2012