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%I #8 Jun 11 2018 04:17:52
%S 159,8479,474853,26702419,1502057181,84495589507,4753161432989,
%T 267381383420963,15041106058843389,846113027177563139,
%U 47596716094317460573,2677476070233122179939,150617073927319718240061
%N Number of (n+1) X 3 0..3 arrays with every 2 X 2 subblock having unequal diagonal elements or unequal antidiagonal elements, and new values 0..3 introduced in row major order.
%C Column 2 of A205170.
%H R. H. Hardin, <a href="/A205164/b205164.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 62*a(n-1) -329*a(n-2) +324*a(n-3) -84*a(n-4).
%F Empirical g.f.: x*(159 - 1379*x + 1466*x^2 - 392*x^3) / ((1 - 5*x + 2*x^2)*(1 - 57*x + 42*x^2)). - _Colin Barker_, Jun 11 2018
%e Some solutions for n=4:
%e ..0..1..0....0..1..1....0..0..0....0..0..0....0..0..0....0..0..1....0..0..0
%e ..0..1..0....0..2..1....0..1..1....0..1..0....0..1..1....0..1..1....0..1..1
%e ..0..1..0....1..1..0....2..0..2....2..2..1....1..1..0....2..2..1....2..3..2
%e ..0..1..1....3..2..3....2..1..0....1..3..2....0..0..2....0..3..1....3..1..1
%e ..0..0..0....3..0..0....3..2..2....0..1..0....0..1..2....0..1..0....1..0..3
%Y Cf. A205170.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 22 2012