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A206391 Number of n X 3 0..5 arrays with no element equal to another within a city block distance of two, and new values 0..5 introduced in row major order.

%I A206391 #12 Jun 16 2018 13:44:28
%S A206391 1,4,26,206,1592,12428,96632,752552,5856992,45595664,354918176,
%T A206391 2762807264,21506309504,167411006144,1303169775488,10144214859392,
%U A206391 78965192918528,614685592164608,4784872150020608,37246687385693696
%N A206391 Number of n X 3 0..5 arrays with no element equal to another within a city block distance of two, and new values 0..5 introduced in row major order.
%C A206391 Column 3 of A206396.
%H A206391 R. H. Hardin, <a href="/A206391/b206391.txt">Table of n, a(n) for n = 1..210</a>
%F A206391 Empirical: a(n) = 6*a(n-1) + 18*a(n-2) - 32*a(n-3) for n>5.
%F A206391 Empirical g.f.: x*(1 - 2*x - 16*x^2 + 10*x^3 + 16*x^4) / (1 - 6*x - 18*x^2 + 32*x^3). - _Colin Barker_, Jun 16 2018
%e A206391 Some solutions for n=4:
%e A206391   0 1 2    0 1 2    0 1 2    0 1 2    0 1 2    0 1 2    0 1 2
%e A206391   3 4 5    3 4 5    2 3 4    2 3 0    2 3 4    3 4 5    2 3 0
%e A206391   5 0 1    1 0 3    4 5 1    4 5 1    1 5 0    1 0 3    1 4 5
%e A206391   4 3 2    2 5 1    3 2 0    0 2 4    4 2 3    4 5 1    5 0 1
%Y A206391 Cf. A206396.
%K A206391 nonn
%O A206391 1,2
%A A206391 _R. H. Hardin_, Feb 07 2012