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

1,1

Links

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

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

Example

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

Crossrefs

Column 2 of A233230.

Sequence in context: A351274 A228476 A308449 * A167014 A370909 A366736

Adjacent sequences: A233221 A233222 A233223 * A233225 A233226 A233227

Keyword

nonn

Author

R. H. Hardin, Dec 06 2013

Status

approved