A233224 Number of n X 2 0..5 arrays with no element x(i,j) adjacent to value 5-x(i,j) horizontally, diagonally, antidiagonally or vertically, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order.

2, 14, 174, 2541, 39203, 616454, 9757236, 154782591, 2457231917, 39019481264, 619661480574, 9841023112761, 156289684281383, 2482114628442074, 39419748363507816, 626045687116778451, 9942561014884521857

Offset: 1

Author

R. H. Hardin, Dec 06 2013

Keywords

• nonn

Examples

			Some solutions for n=5:
..0..1....0..0....0..1....0..1....0..1....0..0....0..0....0..0....0..1....0..1
..1..1....1..2....0..0....0..2....1..1....1..2....1..2....1..0....2..2....0..2
..2..0....5..1....0..4....2..2....2..2....1..2....2..2....0..0....2..4....2..0
..1..2....1..5....2..0....4..4....2..2....5..5....1..0....2..2....4..4....1..0
..0..0....5..1....1..2....4..5....1..1....4..5....1..1....1..5....5..5....0..1
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Crossrefs

Column 2 of A233230.

Formula

Empirical: a(n) = 21*a(n-1) - 79*a(n-2) - 41*a(n-3) + 72*a(n-4) + 28*a(n-5).

Empirical g.f.: x*(2 - 28*x + 38*x^2 + 75*x^3 + 18*x^4) / ((1 - x)*(1 - 5*x - 2*x^2)*(1 - 15*x - 14*x^2)). - Colin Barker, Oct 10 2018