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%I #9 Jul 15 2018 06:53:20
%S 1,10,101,910,7545,59178,447429,3300982,23953969,171879010,1223834045,
%T 8668104046,61170701289,430597896090,3025851581877,21237517730278,
%U 148936511331361,1043880899831122,7313575755465773,51226014364080862
%N Number of (n+1) X 2 0..3 arrays containing all values 0..3 with every 2 X 2 subblock having two or four distinct values, and new values 0..3 introduced in row major order.
%C Column 1 of A210174.
%H R. H. Hardin, <a href="/A210167/b210167.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 14*a(n-1) - 55*a(n-2) + 22*a(n-3) + 132*a(n-4) + 56*a(n-5).
%F Empirical g.f.: x*(1 - 4*x + 16*x^2 + 24*x^3 + 8*x^4) / ((1 - 7*x)*(1 - 3*x - 2*x^2)*(1 - 4*x - 4*x^2)). - _Colin Barker_, Jul 15 2018
%e Some solutions for n=4:
%e ..0..0....0..1....0..0....0..0....0..0....0..1....0..0....0..0....0..0....0..0
%e ..0..1....2..3....1..0....0..1....0..1....1..0....1..0....1..0....0..1....0..1
%e ..1..0....2..3....1..0....1..0....0..0....0..0....0..0....0..1....0..0....1..1
%e ..2..3....1..0....0..1....0..1....1..0....2..0....2..0....0..1....0..1....0..1
%e ..1..0....1..0....2..3....2..3....2..3....1..3....3..1....2..3....2..3....2..3
%Y Cf. A210174.
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 18 2012
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