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%I #8 Sep 21 2018 08:14:24
%S 12,1840,6809,15075,29776,57677,113330,228657,473562,1000381,2139866,
%T 4607729,9947906,21481485,46333458,99752209,214296842,459341309,
%U 982407146,2096608977,4465367730,9492005773,20140323170,42660619313
%N Number of defective 4-colorings of an n X 5 0..3 array connected horizontally, vertically, diagonally and antidiagonally with exactly two mistakes, and colors introduced in row-major 0..3 order.
%H R. H. Hardin, <a href="/A229752/b229752.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 9*a(n-1) - 33*a(n-2) + 63*a(n-3) - 66*a(n-4) + 36*a(n-5) - 8*a(n-6) for n>11.
%F Empirical g.f.: x*(12 + 1732*x - 9355*x^2 + 13758*x^3 + 3670*x^4 - 20791*x^5 + 10370*x^6 + 686*x^7 - 1124*x^8 - 440*x^9 + 208*x^10) / ((1 - x)^3*(1 - 2*x)^3). - _Colin Barker_, Sep 21 2018
%e Some solutions for n=3:
%e ..0..1..2..1..2....0..1..2..0..1....0..1..2..0..3....0..1..0..2..1
%e ..2..1..0..3..0....2..3..2..3..2....3..3..2..1..2....2..3..0..3..0
%e ..2..3..2..1..2....1..0..1..3..0....0..1..0..3..0....0..1..1..2..1
%Y Column 5 of A229755.
%K nonn
%O 1,1
%A _R. H. Hardin_, Sep 28 2013
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