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%I #13 Jul 15 2018 04:28:00
%S 8,81,897,10019,111993,1251951,13995437,156453699,1748981553,
%T 19551704471,218566712277,2443337243979,27313843108313,
%U 305338948679391,3413356121689917,38157595235947859,426560259838806273
%N Number of (n+1) X 2 0..3 arrays with every 2 X 2 subblock having one, three or four distinct values, and new values 0..3 introduced in row major order.
%C Column 1 of A210134.
%H R. H. Hardin, <a href="/A210127/b210127.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 12*a(n-1) - 9*a(n-2) - 2*a(n-3).
%F Empirical g.f.: x*(8 - 15*x - 3*x^2) / ((1 - x)*(1 - 11*x - 2*x^2)). - _Colin Barker_, Jul 14 2018
%e Some solutions for n=4:
%e 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 1
%e 0 0 1 2 0 0 0 0 0 0 1 2 2 2 0 2 0 0 1 2
%e 0 0 0 1 0 0 0 0 0 0 3 1 1 0 0 1 1 2 2 3
%e 1 2 1 3 0 0 1 2 1 2 1 0 0 3 1 2 2 0 1 1
%e 3 3 3 0 0 0 1 0 2 0 0 2 0 1 2 3 2 3 0 3
%Y Cf. A210134.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 17 2012