A229530 - OEIS

%I #8 Sep 18 2018 12:14:40

%S 6,36,361,3064,24344,185808,1379512,10036352,71892488,508702512,

%T 3563926872,24764330720,170893859240,1172387842960,8002259515128,

%U 54379352988992,368101566941512,2483167144168432,16699758317833368

%N Number of defective 3-colorings of an n X 4 0..2 array connected horizontally, diagonally and antidiagonally with exactly one mistake, and colors introduced in row-major 0..2 order.

%H R. H. Hardin, <a href="/A229530/b229530.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 14*a(n-1) - 57*a(n-2) + 56*a(n-3) - 16*a(n-4) for n>5.

%F Empirical g.f.: x*(6 - 48*x + 199*x^2 - 274*x^3 + 105*x^4) / (1 - 7*x + 4*x^2)^2. - _Colin Barker_, Sep 18 2018

%e Some solutions for n=4:

%e ..0..1..0..2....0..1..0..2....0..1..2..1....0..1..0..1....0..1..0..2

%e ..0..1..0..1....0..2..0..1....2..1..0..1....0..2..0..2....0..2..0..1

%e ..0..2..0..1....0..1..0..2....2..1..0..2....1..2..1..0....0..1..2..1

%e ..1..1..0..2....0..1..2..1....0..1..2..1....1..2..1..0....2..1..0..1

%Y Column 4 of A229534.

%K nonn

%O 1,1

%A _R. H. Hardin_, Sep 25 2013