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A229691 Number of defective 3-colorings of an nX5 0..2 array connected horizontally and antidiagonally with exactly two mistakes, and colors introduced in row-major 0..2 order.

%I A229691 #8 Jul 23 2025 05:46:12
%S A229691 12,1171,35825,848937,17724789,342532665,6279934941,110801828529,
%T A229691 1898544262293,31786996628745,522316663574733,8450380115641377,
%U A229691 134940473888031045,2130891564532483449,33326706458497564413
%N A229691 Number of defective 3-colorings of an nX5 0..2 array connected horizontally and antidiagonally with exactly two mistakes, and colors introduced in row-major 0..2 order.
%C A229691 Column 5 of A229694
%H A229691 R. H. Hardin, <a href="/A229691/b229691.txt">Table of n, a(n) for n = 1..210</a>
%F A229691 Empirical: a(n) = 45*a(n-1) -729*a(n-2) +4995*a(n-3) -13122*a(n-4) +14580*a(n-5) -5832*a(n-6) for n>7.
%F A229691 Empirical: 12*x -x^2*(-1171+16870*x-90471*x^2+210096*x^3-212220*x^4+81648*x^5) / (18*x^2-15*x+1)^3. - _R. J. Mathar_, Sep 29 2013
%e A229691 Some solutions for n=3
%e A229691 ..0..1..0..1..0....0..1..2..1..0....0..1..0..1..2....0..1..2..0..1
%e A229691 ..0..1..0..1..2....2..1..0..1..2....2..1..2..0..2....0..2..1..0..2
%e A229691 ..0..0..2..1..2....2..1..1..0..2....0..2..1..1..0....1..2..1..1..0
%K A229691 nonn
%O A229691 1,1
%A A229691 _R. H. Hardin_, Sep 27 2013