A233234 Number of n X 3 0..5 arrays with no element x(i,j) adjacent to value 5-x(i,j) horizontally, diagonally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order.

6, 271, 18744, 1409129, 107709266, 8259321811, 633724470764, 48630297616989, 3731839458899046, 286378755661153351, 21976523359713989184, 1686464664689831932049, 129418247854721047490426

Offset

1,1

Links

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

Formula

Empirical: a(n) = 93*a(n-1) - 1273*a(n-2) + 1943*a(n-3) - 882*a(n-4) + 120*a(n-5).

Empirical g.f.: x*(6 - 287*x + 1179*x^2 - 738*x^3 + 120*x^4) / ((1 - x)*(1 - 15*x + 6*x^2)*(1 - 77*x + 20*x^2)). - Colin Barker, Oct 10 2018

Example

Some solutions for n=3:
..0..1..2....0..1..0....0..1..0....0..1..5....0..1..2....0..1..1....0..1..0
..3..4..5....1..2..0....2..1..1....0..2..5....1..2..5....0..1..0....2..4..3
..3..4..3....0..2..0....2..2..5....2..1..0....4..2..5....1..1..2....0..4..4

Crossrefs

Column 3 of A233239.

Sequence in context: A229773 A193983 A348701 * A281694 A250390 A284071

Adjacent sequences: A233231 A233232 A233233 * A233235 A233236 A233237

Keyword

nonn

Author

R. H. Hardin, Dec 06 2013

Status

approved