A233595 Number of (n+2)X(1+2) 0..2 arrays with no increasing sequence of length 3 horizontally, vertically or antidiagonally downwards

15272, 342185, 7610545, 169129037, 3756984641, 83451469774, 1853608731449, 41171843204299, 914496266769293, 20312503043503618, 451174881822359137, 10021353348112998329, 222591120354824691196, 4944123321916955713069

Offset

1,1

Comments

Column 1 of A233602

Links

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

Formula

Empirical: a(n) = 25*a(n-1) +2*a(n-2) -1549*a(n-3) +1359*a(n-4) +35322*a(n-5) -27013*a(n-6) -345233*a(n-7) +159641*a(n-8) +1285880*a(n-9) -375833*a(n-10) -2431870*a(n-11) +439479*a(n-12) +2628508*a(n-13) -276145*a(n-14) -1679602*a(n-15) +92032*a(n-16) +613439*a(n-17) -14601*a(n-18) -111609*a(n-19) +738*a(n-20) +6490*a(n-21) +22*a(n-22) -121*a(n-23)

Example

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

Crossrefs

Sequence in context: A252318 A233602 A233603 * A233594 A064982 A204317

Adjacent sequences: A233592 A233593 A233594 * A233596 A233597 A233598

Keyword

nonn

Author

R. H. Hardin, Dec 14 2013

Status

approved