A233613 Number of (n+2)X(3+2) 0..2 arrays with no increasing sequence of length 3 horizontally or diagonally downwards

9120456, 1777375908, 345855899520, 67296801927960, 13094412982589016, 2547870958491036012, 495756869782694668272, 96462841432650917213520, 18769441889238121771723944, 3652100058091248774988665012

Offset

1,1

Comments

Column 3 of A233618

Links

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

Formula

Empirical: a(n) = 216*a(n-1) -3582*a(n-2) -127224*a(n-3) +2457495*a(n-4) +21025008*a(n-5) -505022364*a(n-6) -258645312*a(n-7) +37921168656*a(n-8) -199403171712*a(n-9) +265276451520*a(n-10) +271825694208*a(n-11) -396718580736*a(n-12)

Example

Some solutions for n=1
..0..0..0..0..1....0..0..0..0..0....0..0..0..0..2....0..0..0..0..2
..0..2..1..0..2....1..2..1..1..0....1..1..0..2..0....1..2..1..0..0
..1..2..0..0..1....0..2..2..1..1....0..1..0..2..1....0..0..1..0..1

Crossrefs

Sequence in context: A186139 A335581 A015350 * A172620 A172711 A187675

Adjacent sequences: A233610 A233611 A233612 * A233614 A233615 A233616

Keyword

nonn

Author

R. H. Hardin, Dec 14 2013

Status

approved