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%I #10 Mar 07 2018 02:31:12
%S 5,32,244,1904,14976,118096,931968,7356288,58068800,458389760,
%T 3618506752,28564366592,225486229504,1779981604864,14051122574336,
%U 110919150841856,875592537571328,6911901929525248,54562352063938560,430713614487224320
%N Number of n X 4 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 Column 4 of A208050.
%H R. H. Hardin, <a href="/A208046/b208046.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 12*a(n-1) - 40*a(n-2) + 68*a(n-3) - 64*a(n-4) for n>5.
%F Empirical g.f.: x*(5 - 28*x + 60*x^2 - 84*x^3 + 32*x^4) / (1 - 12*x + 40*x^2 - 68*x^3 + 64*x^4). - _Colin Barker_, Mar 06 2018
%e Some solutions for n=4:
%e 0 1 2 1 0 1 2 0 0 1 0 1 0 1 2 3 0 1 2 3
%e 2 3 0 2 2 0 1 2 2 3 2 3 2 3 0 1 2 3 0 1
%e 1 2 1 3 1 3 0 1 0 1 0 1 0 1 3 0 1 2 3 2
%e 3 0 2 0 2 1 2 3 2 3 2 0 2 0 2 1 3 1 0 1
%Y Cf. A208050.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 22 2012
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