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A233141 Number of n X 2 0..5 arrays with no element x(i,j) adjacent to value 5-x(i,j) horizontally, antidiagonally or vertically, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order.

%I A233141 #8 Oct 08 2018 10:20:24
%S A233141 2,16,225,3727,65120,1158334,20726079,371568349,6665506622,
%T A233141 119595908140,2145992981277,38507882245867,690993582249116,
%U A233141 12399363162575962,222497465035339899,3992554551056534713,71643481793789018234
%N A233141 Number of n X 2 0..5 arrays with no element x(i,j) adjacent to value 5-x(i,j) horizontally, antidiagonally or vertically, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order.
%H A233141 R. H. Hardin, <a href="/A233141/b233141.txt">Table of n, a(n) for n = 1..210</a>
%F A233141 Empirical: a(n) = 25*a(n-1) - 134*a(n-2) + 134*a(n-3) - 25*a(n-4) +a(n-5).
%F A233141 Empirical g.f.: x*(2 - 34*x + 93*x^2 - 22*x^3 + x^4) / ((1 - x)*(1 - 18*x + x^2)*(1 - 6*x + x^2)). - _Colin Barker_, Oct 08 2018
%e A233141 Some solutions for n=5:
%e A233141 ..0..1....0..0....0..0....0..1....0..1....0..1....0..0....0..1....0..1....0..1
%e A233141 ..2..1....1..1....1..2....2..2....0..1....1..0....1..2....2..0....2..5....0..2
%e A233141 ..2..2....2..1....5..4....1..2....0..1....2..0....0..2....2..1....5..5....4..2
%e A233141 ..1..2....5..1....3..3....0..1....0..2....4..0....0..0....5..1....2..2....5..2
%e A233141 ..2..1....1..0....4..5....3..5....1..1....4..2....3..0....2..1....2..5....2..1
%Y A233141 Column 2 of A233147.
%K A233141 nonn
%O A233141 1,1
%A A233141 _R. H. Hardin_, Dec 04 2013